LIVES OF THE ELECTRICIANS.
LIVES
OF
THE ELECTRICIANS:
PROFESSORS
TYNDALL, WHEATSTONE, AND MORSE.
FIRST SERIES.
BY
WILLIAM T. JEANS.
“The electric telegraph is the most precious gift which Science has
given to civilisation.”—Sir D. Brewster.
LONDON:
WHITTAKER & CO., 2, White Hart Street,
Paternoster Square, E. C.
GEORGE BELL & SONS, York Street, Covent Garden.
1887.
Richard Clay and Sons,
london and bungay.
CONTENTS.
INTRODUCTION.
Use of lives of electricians—World-wide distribution of electricians—Eminent authorities on biographical studies Pages [ix-xvi]
PROFESSOR TYNDALL.
CHAPTER I.
Position as a scientist—Origin and early career—Work on Ordnance Survey, and as a teacher—Student life at Marburg—Sense of duty and early friendships Pages [1-20]
CHAPTER II.
Subjects of study in Germany—Discovery of diamagnetism—Investigation of it—Scientific acquaintances—Early connection with Royal Institution—Slaty cleavage—Glacier phenomena explained Pages [21-41]
CHAPTER III.
Researches on Radiant Heat—Aqueous vapour and new glacial theory—Calorescence—Formation of clouds—Germ theory—Smoke respirator—Experiments on sound and its production by heat Pages [42-59]
CHAPTER IV.
Alpine travels—Ascent of Monte Rosa, Mont Blanc, Weisshorn, Col-du-Géant, and Piz Morteratch—Visit to Vesuvius—An American’s impressions—Visit to America—Exploration of Niagara Falls—Presidental address to British Association Pages [60-83]
CHAPTER V.
Changes at Royal Institution—Development of electricity explained—Experimental illustrations and anecdotes—Reminiscences of Thomas Carlyle—Scientific adviser to the Trinity House Pages [84-104]
PROFESSOR WHEATSTONE.
CHAPTER I.
Forecasts of the telegraph—Early descriptions and history of it—Birth and early achievements of Wheatstone—Enchanted lyre or first telephone—Experiments in audition—Invention of concertina—Velocity of electricity measured—Spectrum analysis—Lightning conductors Pages [105-132]
CHAPTER II.
Origin of telegraph—Early evidences of Wheatstone’s—Working of first needle telegraph—Dispute with Mr. W. F. Cooke as to priority of invention—Wheatstone’s vindication—His electro-magnetic telegraph, magneto-electric machine, electric clock, printing telegraph, chronoscope, method of measuring electricity, and improved needle telegraphs Pages [133-172]
CHAPTER III.
First uses of telegraph—Means of arresting criminals—Early charges for telegraphing—Formation of Electric Telegraph Company—Wheatstone’s magneto-electric exploder—His early experiments with submarine cables—Cable from Dover to Calais—Faraday on Wheatstone’s A.B.C. telegraph instrument—His automatic instruments Pages [173-203]
CHAPTER IV.
Origin of Dynamo—Invention of stereoscope—Improvement by Sir D. Brewster—Illustration of earth’s rotatory motion—Wheatstone’s cryptograph—His minor inventions—Honours conferred on him—His death Pages [204-230]
PROFESSOR MORSE.
CHAPTER I.
Birth and education—Diverted from electricity to art—Labours as an artist in England and America Pages [231-241]
CHAPTER II.
Travels to study art—First conception of Recording Telegraph—Experiments with it in New York—Invention of Relay—His poverty and disappointments—His originality disputed—First exhibitions of his apparatus—Descriptions of it—Foreign patents—Introduction of photography—Congress asked to try his telegraph—Appropriation granted—Experimental line made and opened Pages [242-278]
CHAPTER III.
Morse Telegraph offered to Government and declined—Rapid extension of it by Companies—Determination of longitude; Morse transmitter and sounder—First Atlantic Cable Pages [279-301]
CHAPTER IV.
Rewards of inventors—Morse patents vindicated—Rival inventions—Pioneers of practical telegraphy—Honours and emoluments of Morse—Statue in New York—Last days—Death Pages [302-322]
INTRODUCTION.
Although this work is the first of its kind relating to electricians, its design is neither novel nor tentative. Its object is not only to give a popular account of the most memorable achievements of those men who have succeeded in evolving the laws of electricity, but to convey to unscientific readers some knowledge of the nature of those laws, and the means by which they have been applied to the purposes of man.
In some senses electrical science and its practical applications might be described as the creation of the present century; and the author has been encouraged to adopt this method of giving a popular account of the great and useful work that our electricians have done by the success of a similar work dealing, in like manner, with the men and the inventions that have multiplied and cheapened the production and use of the most useful of metals.[1] An eminent reviewer of that work justly observed that “our inventors might well boast that with a piece of steel and the recent developments of the magnetic force—so far at least as manufactures and commerce are concerned—they have revolutionised the world.” It is this revolution and the men who have effected it, that this work proposes to give an account of, hoping to realise the truth of Tacitus’ observation, that “the age which is most fertile in bright examples is the best qualified to make a fair estimate of them.”
Of books on electricity there is already abundance. They have been poured from the press in yearly increasing numbers. During the present generation the laws of electricity have been explained in every variety of form—in the rigid demonstrations of the geometrician, in the abstract symbolism of the mathematician, in the technical language of numerous text-books, and in the experimental illustrations of popular lecturers. But to the ordinary reader the theorems of the mathematician are written in an unknown tongue; and more elementary books on electricity, to be made interesting to the popular mind, would have to be written in “that language which can give a soul to the objects of sense, and a body to the abstractions of mathematics.” Add to this the fact that, as Prof. C. A. Young puts it, “since 1848 all things have become new in the scientific world. There is a new mathematics and a new astronomy, a new chemistry and a new electricity, a new geology and a new biology. Great voices have spoken, and have transformed the world of thought and research as much as the material products of science have altered the aspects of external life. The telegraph and dynamo-machine have not more changed the conditions of business and industry than the speculations of Darwin and Helmholtz and their compeers have affected those of philosophy and science.”
The conquest of these fresh fields of knowledge has been almost the life’s work of professional scientists; and is that which was said of the past to continue true of the future, that ideas which in one generation are those of the learned few, in the next become those of the educated and middle class, and in the third those of the general public?
Even if no work were necessary to indicate the advances made in electrical knowledge, biographies of the electricians would still be a desideratum. Carlyle has said of art in general that biography is almost the one thing needful. In the literature of electricity, it has hitherto been the one thing lacking. The subject is not destitute of historic as well as scientific interest; and hence it is possible that the general reader may be led to regard it from Terence’s point of view that “whatsoever concerns mankind concerns me.” It is possible, too, that a record of the achievements which have brought electricity to its present state of utility, may impart a reflex interest to that science. “Art is art,” says Carlyle, “yet man also is man. Had the Transfiguration of Raphael been painted without human hand; had it grown merely on the canvas, say by atmospheric influences, as lichen pictures do on rocks—it were a grand picture doubtless; yet nothing like so grand as the picture which on opening our eyes we everywhere in heaven and earth see painted, and everywhere pass over with indifference,—because the Painter was not Man. Think of this; much lies in it. The Vatican is great; yet poor to Chimborazo or the Peak of Teneriffe; its dome is but the foolish chip of an egg-shell, compared with that star-fretted dome where Arcturus and Orion glance for ever; which latter notwithstanding who looks at? The biographic interest is wanting: no Michael Angelo was He who built that ‘Temple of Immensity;’ therefore do we, pitiful Littlenesses as we are, turn rather to wonder and to worship in the little toy-box of a Temple built by our like.” Now it has been well observed that science is to the present age what art was to the middle ages; and such being the case, may not a similar interest to that described by Carlyle attach to the marvellous things done by means of electricity? A great deal is said about electricity, but very little about the men who made it subject to the will of man, who converted it into “the pulse of speech” which annihilates time and space, and who made it “the greatest blessing that science has given to civilisation.” Of them it has often been said that “their line has gone out through all the earth, and their words to the end of the world,” but of their lives not much has been communicated to the general public in a popular form.
The men who have made electricity the handmaid of industry are nearly as widespread as the subtle force with which they have had to deal. The United Kingdom was the birth-place of the monarch of modern machinery—the steam-engine,—and also of the leading inventions in metallurgy which supply the framework of all our manufacturing machinery; but the pioneers and engineers of electricity have been of different nations and tongues. In the infancy of the science no country produced more electricians than Germany; in the discovery and exposition of its subtlest laws, as well as in their application to useful purposes, no country has done more than England; while in the most novel and most extensive use of electrical appliances for industrial purposes the New World may be said to have outstripped the Old. But smaller countries have also made splendid contributions to the general store of knowledge. Volta, the first philosopher who from his youth devoted himself to the study of electricity, and who has given his name to one department of it, was an Italian; so was Galvani, who discovered that a frog was the most sensitive electrometer, and whose name became a synonym for electricity. Oersted, who made himself famous by the discovery of the mutual action of magnets and electrical conductors, was a Dane; while Ampère, whom some writers have called “the Newton of electricity,” and Arago, who discovered the development of magnetism by rotation, were Frenchmen.
Most of these pioneers have already taken their place in the Temple of Science; and this work not being intended to go over beaten ground, it was expected, at the outset, to comprise in one volume sufficient biographies to illustrate the more recent progress of electrical science and its applications to industrial purposes; but the more the writer investigated the subject, the more it grew, not only in magnitude, but in magnetic attractiveness. He found that to give a complete account of the revolution effected by means of electricity would require biographies of the three classes of men,—scientific, engineering, and commercial—that had been instrumental in bringing electricity to its present state of usefulness; while to do justice to these men would require such a varied picture of their lives as would illustrate their marvellous versatility, or their multifarious works, thus showing that they were among the ornaments as well as the benefactors of their race. He was encouraged to begin this work by the success of his previous effort, and he was encouraged to continue it beyond the limit originally intended by experiencing a feeling of pleasure akin to that which led Plutarch to say in the course of his work, that when he first applied himself to the writing of ancient lives it was for the sake of others, but he pursued that study for his own sake: for it was like living and conversing with these illustrious men, when he considered how great and wonderful they were. More recently Lord Bacon said he “could not but wonder that our own times have so little value for what they enjoy, as not more frequently to write the lives of eminent men; for though kings, princes, and great personages are few, yet there are many excellent men who deserve better than vague reports and barren eulogies.” Nor is there any lack of authority as to the value of our subject in the estimation of contemporary schools of thought. An eminent Greek scholar (Dr. Lushington) in addressing the students of Glasgow University as their Lord Rector in 1885, observed that “the hope of adding something more to the store of accomplished good to mankind cheered and upheld many daring pioneers of science, whose venerated names, now become household words, are linked together for ever in the history of human progress, known and honoured throughout the whole civilised world. Yet who in the age of Watt, even in the boldest flights of presaging imagination, could have foretold such wondrous conquests over space and time as the spectroscope, the electric telegraph, and the telephone have revealed?”
The object of this work is to give some account of “such wondrous conquests.” The guiding principle in its compilation has been the maxim of Goethe, that the main object of biography is to exhibit man in relation to the features of his time; and not as Dumas, on the other hand, sarcastically put it, “to trace each man’s innermost life, ascertain whether he was born on a calcareous or a granite soil, learn whether his ancestors and himself have drunk wine, cider, or beer, or eaten meat, fish, or vegetables—nay, to penetrate the meanest details of his existence, to descend from the heights of criticism and from a scientific system to the gratification of a paltry curiosity.”
This volume opens with an account of the labours of the physicist who made a special study of the phenomena of magnetism, electricity, and co-relative forces; and in the course of it occasion is taken to explain certain elementary principles of these forces. It then proceeds to give, in the life of Professor Wheatstone, an account of some of the methods by which such scientific principles were made serviceable to man; and it concludes with an account of the man who made it the labour of his life to produce a telegraphic apparatus and alphabet which have found universal favour. Technical language has been avoided as far as possible, and yet it is hoped that the descriptions given of electrical laws and mechanism will convey substantially correct impressions, without entering into elaborate details or straining after scientific exactness. While it may thus become a means of imparting to unscientific readers some knowledge of the history of electrical science and engineering, it is hoped that the narrative will be found sufficiently instructive to point a moral to that wider class of readers who take a sympathetic interest in the struggles and achievements of those unobtrusive but beneficent men, “who, departing, leave behind them foot-prints on the sands of time.”
FOOTNOTES:
[1] The Creators of the Age of Steel.
LIVES OF THE ELECTRICIANS.
PROFESSOR TYNDALL.
CHAPTER I.
“Precious is the new light of knowledge which our Teacher conquers for us; yet small to the new light of Love which also we derive from him: the most important element of any man’s performance is the Life he has accomplished.”—Carlyle.
The position of Professor Tyndall in the world of science is somewhat unique. He is one of our most popular teachers of physical science; he is one of our most successful experimentalists; and he is one of our most attractive writers. By his discoveries he has largely extended our knowledge of the laws of Nature; by his teaching and writings he has probably done more than any other man in England to kindle a love of science among the masses; and by his life he has set an example to students of science which cannot be too widely known or appreciated. There are men who have made greater and more useful discoveries in science, but few have made more interesting discoveries. There are men whose achievements have been more highly esteemed by the devotees of pure science, but rarely has a scientific man been more popular outside the scientific world. There are men whose culture has been broader and deeper, but who have nevertheless lacked his facility of exposition and gracefulness of diction. The goddess of Science, which ofttimes was presented to the public with the repulsive severity of a skeleton, he has clothed with flesh and blood, making her countenance appear radiant with the glow of poesy, and susceptible even to a touch of human sympathy; while amongst scientific contemporaries, though he does not rank as one of those creative minds that mark an epoch in the history of physical philosophy, he may yet be said to have “built many a stone into the great fabric of science, which gives it an ever-broader support and an ever-growing height without its appearing to a fresh observer as a special and distinctive work due to the sole exertion of any one scientific man.” He commenced his scientific career at the time when Sir William Grove began to elaborate that theory of the co-relation of the physical sciences which Newton suspected and Faraday elucidated; namely, “that the various affections of matter, heat, light, electricity, magnetism, chemical affinity, and motion are all correlative or have a reciprocal dependence: that neither, taken abstractedly, can be said to be the essential or proximate cause of the others, but that either may, as a force, produce the others; thus heat may mediately produce electricity, electricity may produce heat; and so of the rest.” Professor Tyndall has extended or simplified our knowledge of these forces. Indeed he may be said to have revealed some hidden links in the chain of causation. He has extended and consolidated our knowledge of magnetism; as an explorer and discoverer in the domain of radiant heat he stands almost alone; and as a lecturer and experimentalist he has probably done more than any other man to popularise the science of electricity.
There is a growing tendency in the present day to appreciate personal achievement more highly than ancient lineage; and it is becoming more a matter of boast in the intellectual world to say that an eminent man was self-made than to say he was of noble birth. The subject of this memoir can boast both of high descent and of lowly birth. “I am distantly connected,” he says, “with one William Tyndale, who was rash enough to boast, and to make good his boast, that he would place an open Bible within reach of every ploughboy in England. His first reward was exile, and then a subterranean cell in the Castle of Vilvorden. It was a cold cell, and he humbly, but vainly, prayed for his coat to cover him and for his books to occupy him. In due time he was taken from the cell and set upright against a post. Round neck and post was placed a chain, which being cunningly twisted, the life was squeezed out of him. A bonfire was made of his body afterwards.”
It is said that the martyr Tyndale was descended from the ancient barons of Tyndale in Northumberland, whose title eventually passed into the family of the Percies, and that the said ancestors, leaving the north during the war of the Roses, afterwards sought and found refuge in Gloucestershire. Of one of these refugees the martyr of Vilvorden was the great-grandson, and was, it is believed, born in 1484. Both family tradition and documents show that some members of the Tyndale family, who were cloth manufacturers, migrated from Gloucestershire to the county of Wexford in Ireland about two centuries ago. One William Tyndale landed on the coast of Ireland in 1670, and his descendants in later years became scattered over Wexford, Waterford, and Carlow. Their fortunes varied; but for our purpose it is sufficient to know that the grandfather of the Professor had a small estate in Wexford; and that on removing thence to the village of Leighlin Bridge on the banks of the Barrow, county Carlow, he continued to prosper until he got into easy circumstances. But throughout the whole race of Tyndale, from the Martyr down to the Professor, intellectual independence appears to have been preferred to worldly independence, and it was the exercise of this trait that cost the Professor the small patrimony which his grandfather had acquired. A high sense of rectitude and a benevolent disposition are not incompatible with excessive susceptibility to opposition; and hence persons of high principles sometimes stand like adamant on points that to worldly minds appear too trifling even for controversy, much less for self-sacrifice. Though the opinions of the Tyndales may have differed, the leading principles that governed their conduct appear to have been maintained with remarkable consistency and self-denial. John Tyndale, the father of the Professor, differed in opinion with his own father, William Tyndale of Leighlin Bridge, on some point that has long since been forgotten, but in consequence of that difference William revoked his will in favour of his first-born son, John, and left his property to two sons of a second marriage.
Leighlin Bridge, where John Tyndall was born in humble circumstances in 1820, was a thriving town of 2,000 inhabitants, forty-six miles south-west of Dublin. It was then the entrepot where the great southern road from Dublin to Waterford and Cork crossed the Barrow, and it has consequently been declining ever since the development of the railway system diverted the traffic. It was not destitute of historical associations, which to the Irish mind were of an exciting character. Nor was the country destitute of natural attractions. When Tyndall was a youth its general aspect was described as soft and agreeable, with little of forcible or imposing scenery, yet free from those harsh features which so frequently mar the effect of Irish landscape. In some parts it so closely resembled the “champaign, ornate, and agreeable districts of central England,” that it was said constantly to remind an English traveller passing through the country of the “equable, grateful scenery, the calm and soft-faced prettiness of territorial view to which his mind had been accustomed.”
Yet to the ordinary English reader its loneliness would appear to have little that was likely to fire the opening mind of the Apostle of Physical Science. It need not, however, appear an inauspicious birthplace to those who believe that it is no mere accident that has made great enthusiasts generally proceed from lonely or sterile countries.
Let us therefore look a little more into this home from which so much light was to be reflected in after years by its then youngest inhabitant. The Professor’s father, being left dependent on his own resources, early joined the Irish Constabulary force and remained in it for several years. He was regarded as a man of exceptional ability and unswerving integrity, and was respected by all who knew him. A sturdy politician and a zealous Orangeman, he preserved as a precious relic a bit of flag which was said to have fluttered at the Battle of the Boyne. In such a man Protestantism was no mere hereditary faith. It was evolved from his own inner consciousness, and was part of his intellectual being. His earnest and capacious mind had mastered the works of Tillotson, Jeremy Taylor, Chillingworth, and other writers who were not only the pillars of the Protestant faith, but still remain unsurpassed as masters of English prose. In our own day men of respectable theological attainments are content to reflect, in lunar-like scintillations, the intellectual splendour, the massive diction, the rich and glowing periods that adorn their pages; and no better evidence could be given of the fine intelligence of John Tyndall, of Leighlin Bridge, than to say that his delight was in the works of these great men. It is the fashion nowadays for critics of the “newspaper” school to sneer at their “pompous grandeur,” but it is those living writers who in elevation of thought and graces of style show the greatest affinity to them that are the most popular. It was with such works that John Tyndall, père, sought to imbue the mind of his only surviving son; and the subtle thoughts and inspiring sentiments which he gathered from such classic ground must have had an invigorating effect on his son’s susceptible mind. Besides his early familiarity with the works of these powerful thinkers, it is said that he soon knew the Bible almost by heart. This species of intellectual discipline has sometimes been pointed to as presenting a strange contrast with his excursions in later life into those regions of natural philosophy which have sometimes been regarded as antagonistic to theology. But it is more than probable that this early training did much to model and chasten the rich, transparent, simple language in which he has so beautifully expounded the laws of Nature. There is high authority for saying that he could have had no better model. Alexander von Humboldt, after reviewing the whole course of ancient literature for “images reflected by the external world on the imagination,” says that “as descriptions of nature the writings of the Old Testament are a faithful reflection of the character of the country in which they were composed, of the alternations of barrenness and fruitfulness, and of the Alpine forests by which the land of Palestine was characterised. The epic or historical narratives are marked by a graceful simplicity, almost more unadorned than those of Herodotus, and most true to nature. Their lyrical poetry is more adorned, and develops a rich and animated conception of the life of nature. It might almost be said that one single psalm (the 104th) represents the image of the whole cosmos.... The meteorological processes which take place in the atmosphere, the formation and solution of vapour, according to the changing direction of the wind, the play of its colours, the generation of hail, and the rolling thunder are described with individualising accuracy, and many questions are propounded which we in our present state of physical knowledge may indeed be able to express under more scientific definitions, but scarcely to answer satisfactorily.” Most of our great writers have acknowledged that the literature that first made a lasting impression on their mind materially influenced their style of writing, and in the writings of Professor Tyndall will be found a good deal of the beautiful simplicity and poetic feeling which abound in Hebrew literature.
The origin of his love of nature is a problem that has exercised his own mind. “I have sometimes tried,” he says, “to trace the genesis of the interest which I take in fine scenery. It cannot be wholly due to my early associations; for as a boy I loved nature, and hence to account for that love of nature I must fall back upon something earlier than my own birth. The forgotten associations of a foregone ancestry are probably the most potent elements in the feeling.” He then accepts as exceedingly likely Mr. Herbert Spencer’s idea that the mental habits and pleasurable activities of preceding generations had descended with considerable force to him. He has, indeed, repeatedly supported the view that intellectual character is largely formed from ancestral peculiarities; and if that be so, he may surely be said to have reproduced some of the higher mental characteristics of the Irish race with marvellous exactness. “In the Celtic genius,” says Michelet, “there is a feeling repugnant to mysticism, and which hardens itself against the mild and winning word, refusing to lose itself in the bosom of the moral God. The genius of the Celts is powerfully urged towards the material and natural; and this proneness to the material has hindered them from easily acceding to laws founded on an abstract notion.... In the seventh century St. Columbanus said: ‘The Irish are better astronomers than the Romans.’ It was a disciple of his, also an Irishman, Virgil, Bishop of Saltzburg, who first affirmed the rotundity of the earth and the existence of the Antipodes. All the sciences were at this period cultivated with much renown in the Scotch and Irish monasteries.” These characteristics appear to predominate in the Irish intellect at the present day. Physical science, which is the glory of our age, owes much to Ireland. Sir William Thomson, one of the most versatile and brilliant of natural philosophers, was born in Ireland; so was George Gabriel Stokes, one of Newton’s worthiest successors in the Lucasian chair of mathematics at Cambridge as well as President of the Royal Society; Henry Smith, the greatest mathematician of his time at Oxford, who died in 1883, was an Irishman; Sir William Rowan Hamilton, the Astronomer-Royal for Ireland, was also one of Ireland’s most precocious sons; and in such a constellation of Irish genius Professor Tyndall excels as a popular expositor of the laws of nature.
At the age of seven he began to show his natural taste for the works of nature, and his father gave him glowing accounts of the achievements of Newton as
“That sun of science, whose meridian ray
Kindled the gloom of nature into day.”
A good education was the only patrimony which his father could bestow upon him. He was therefore sent to the best school within reach, and remained at it till his nineteenth year. In his earlier schooldays he preferred physical to mental exercises, and thus became expert in running, swimming, climbing, and other sports. The branch of study in which he excelled was mathematics. Under the tuition of a good teacher in an Irish national school, he acquired a knowledge of elementary algebra, geometry, trigonometry, and conic sections. His favourite “arithmetic” was the treatise of Professor Thomson, the father of Sir William Thomson, who in later years became one of his most brilliant contemporaries. At the age of seventeen he showed exceptional facility in solving geometrical problems, and on his way home from school, in company with his teacher, he would work out demonstrations on the snow in winter. But even that accessory he became able to dispense with; for he could so clearly present the relations of space to his mind without the aid of diagrams, that he was able to draw mentally the lines illustrating the solution of complex problems and to preserve this mental image so distinctly that he could reason upon it as correctly as on the diagrams drawn upon paper required by ordinary students. When he came to solid geometry he was able by means of this power of mental representation to dispense with models, which to other students were indispensable.
His powers of reasoning were not confined to mathematics. In his youth he was accustomed to debate with his father the points of doctrine that divide the Protestant from the Roman Catholic Church, reasoning high “of Providence, fore-knowledge, will, and fate.” Sometimes the son took the Protestant side and at other times the Romish side; and in either case he showed much dialectical skill and theological knowledge. He also took more than ordinary interest in the study of English grammar, which he has described as being to his youthful mind a discipline of the highest value and a source of unfailing delight.
Leaving school in April, 1839, he joined a division of the Ordnance Survey then stationed in that district, under the command of Lieut. Geo. Wynne, of the Royal Engineers, who afterwards became an intimate friend of his, and to whom he has frequently expressed his obligation for acts of kindness that promoted his welfare in after life. About that time a good deal of astonishment was publicly expressed at the mathematical powers of one of the many boys employed in calculations on the Ordnance Survey; his name was Alexander Gwin, a native of Derry, and it was reported that at the age of eight years he had got by rote the fractional logarithms from 1 to 1,000, which he could repeat in regular rotation, or otherwise. His rapidity and correctness in calculating trigonometrical distances, triangles, &c., were extraordinary: he could make a return, in acres, roods, and perches, in less than one minute of any quantity of land, on receiving the surveyor’s chained distances; a calculation which the greatest arithmetician would take nearly an hour to do, and would not be so sure of accuracy at the end of that time.
The intention of young Tyndall was to become a civil engineer, which then appeared a most attractive profession to him. As a preliminary qualification he determined to master all the operations of the surveyors. Draftsmen being the best paid, he worked as a draftsman, but applied himself so well to learning the whole business that he soon became able to do the work of the computor, the surveyor, and the trigonometrical observer. He then asked to be allowed to go on field-work, and his desire was granted. In 1841, while he was stationed at Cork, a circumstance occurred which may be described as the turning point in his career. He worked at mapping in company with a gentleman, who, assuming a paternal interest in him, one day, asked the young and promising surveyor how he employed his leisure hours. Dissatisfied with the account given, the gentleman said to him: “You have five hours a day at your disposal, and this time ought to be devoted to study. Had I, when I was your age, had a friend to advise me as I now advise you, instead of being in my present subordinate position, I should be the equal of the director of the Survey.” Pregnant words! Next morning young Tyndall was at his books by five o’clock, and the studious habits then commenced he continued for twelve years.
Next year he was in Preston, and there becoming a member of the Preston Mechanics’ Institute he attended its lectures and made use of its library. One experiment which he saw there he never forgot. In a lecture on respiration, Surgeon Cortess showed the changes produced by the passage of air through the lungs, and in order to illustrate the fact that what went in as free oxygen came out in carbonic acid, he forced his breath through lime water in a flask by means of a glass tube dipped into it; the carbonic acid from the lungs converted the dissolved lime into carbonate of lime, which being practically insoluble was precipitated. All this, he says, was predicted beforehand by the lecturer, “but the delight with which I saw this prediction fulfilled by the conversion of the limpid lime-water into a turbid mixture of chalk and water remains with me as a memory to the present hour” (1884.)
His diligence in study he was soon able to turn to good account. On one occasion there was a dearth of men capable of making trigonometrical observations when such observations were required. Tyndall offered his services in that department; but the offer was not readily accepted. His superiors hesitated to intrust him with a theodolite on account of his inexperience in work of that description: and indeed there were bets made against his chances of success. However, being allowed to try his hand at it, he at once took his theodolite into an open field, where he examined all its parts, and studied their uses. He then made the trigonometrical observations prescribed to him, and when they were compared with the measurement previously made on a larger scale, his work was pronounced to have been successfully done. When he quitted the Ordnance Survey in 1843 he had practically mastered all its operations.
The pay upon the Ordnance Survey, however, was very small, but having ulterior objects in view, he considered the instruction received as some set-off to the smallness of the pay. In order to “prevent some young men from considering their fate specially hard, or from being daunted, because from a very low level they had to climb a very steep hill,” he has stated that on quitting the Ordnance Survey in 1843, his salary was a little under twenty shillings a week, adding, “I have often wondered since at the amount of genuine happiness which a young fellow, of regular habits, not caring for either pipe or mug, may extract even from pay like that.”
In 1844 affairs in this country did not look very tempting to him, and he therefore resolved to go to America, whither some relatives had emigrated early in the century. He had actually made preparations for going there before some of his friends succeeded in dissuading him from it. A sudden outburst of activity in railway construction at the same time opened up a brighter prospect at home. After a pause, he says, there came the mad time of the railway mania, when he was able to turn to account the knowledge he had gained upon the Ordnance Survey; in Staffordshire, Cheshire, Lancashire, Durham, and Yorkshire especially, he was in the thick of the fray.
As a workman at that period he has been highly spoken of by his contemporaries. One of them has stated that “Extreme caution and accuracy, together with dauntless perseverance under difficulties, characterised the performance of every piece of work he took in hand. Habitually, indeed, he pushed verification beyond the limits of all ordinary prudence, and, on returning from a hard day’s work, he has been known to retrace his steps for miles in order to assure himself of the security of some ‘bench mark,’ upon whose permanence the accuracy of his levels depended. Previous to one of those unpostponable thirtieths of November, when all railway plans and sections had to be deposited at the Board of Works, a series of levels had to be completed near Keighley in Yorkshire, and Manchester reached before midnight. The weather was stormy beyond description; levelling staves snapped in twain before the violent gusts of wind; and level and leveller were in constant peril of being overturned by the force of the hurricane. Assistants grumbled ‘Impossible,’ and were only shamed into submissive persistence by that stern resolution which, before nightfall, triumphed over all obstacles.”
Of these stirring scenes the Professor has given a graphic account. He says:—“It was a time of terrible toil. The day’s work in the field usually began and ended with the day’s light, while frequently in the office, and more especially as the awful 30th of November—the latest date at which plans and sections of projected lines could be deposited at the Board of Trade—drew near, there was little difference between day and night, every hour of the twenty-four being absorbed in the work of preparation. Strong men were broken down by the strain and labour of that arduous time. Many pushed through, and are still among us in robust vigour; but some collapsed, while others retired with large fortunes, but with intellects so shattered that, instead of taking their places in the front rank of English statesmen, as their abilities entitled them to do, they sought rest for their brains in the quiet lives of country gentlemen. In my own modest sphere I well remember the refreshment I occasionally derived from five minutes’ sleep on a deal table, with Babbage and Callet’s Logarithms under my head for a pillow. On a certain day, under grave penalties, certain levels had to be finished, and this particular day was one of agony to me. The atmosphere seemed filled with mocking demons, laughing at the vanity of my efforts to get the work done. My levelling staves were snapped, and my theodolite was overthrown by the storm. When things are at their worst a kind of anger often takes the place of fear. It was so in the present instance; I pushed doggedly on, and just at nightfall, when barely able to read the figures on my levelling staff, I planted my last ‘benchmark’ on a tombstone in Haworth Churchyard. Close at hand was the vicarage of Mr. Brontë, where the genius was nursed which soon afterwards burst forth and astonished the world. It was a time of mad unrest—of downright money mania. In private residences and public halls, in London reception rooms, in hotels and the stables of hotels, among gipsies and costermongers, nothing was spoken of but the state of the share market, the prospects of projected lines, the good fortune of the ostler or potboy who by a lucky stroke of business had cleared £10,000. High and low, rich and poor, joined in the reckless game. During my professional connection with railways I endured three weeks’ misery. It was not defeated ambition; it was not a rejected suit; it was not the hardship endured in either office or field; but it was the possession of certain shares purchased in one of the lines then afloat. The share list of the day proved the winding-sheet of my peace of mind. I was haunted by the Stock Exchange. I became at last so savage with myself that I went to my brokers and put away, without gain or loss, the shares as an accursed thing.”
When in Halifax in 1845 he attended a lecture which was delivered by Mr. George Dawson, and which appeared to make a lasting impression on his mind. That popular lecturer then defined duty as a debt owed; and with reference to the Chartist doctrine of “levelling” then in vogue, he said: Supposing two men to be equal at night, and that one rises at six while the other sleeps till nine, what becomes of the gospel of levelling then? The Professor regarded these as the words of Nature, and there was, according to his impression, “a kindling vigour in the lecturer’s words that must have strengthened the sense of duty in the minds of those who heard him.”
It was while working in Yorkshire about that time that he first met Mr. T. A. Hirst, then an articled pupil, who became one of his most intimate friends, and who afterwards became Professor of Mathematics in University College, London. At that time, too, Sir John Hawkshaw, who afterwards was Prof. Tyndall’s successor as President of the British Association, was chief engineer on the Manchester and Leeds Railway, and it was in his Manchester office that Tyndall spent the last days of his railway life. A calm followed the storm of competition just described; work became scarce, and the prospects of engineers were once more overcast.
In these circumstances he accepted, in 1847, an appointment as a teacher in Queenswood College, Hampshire. The well-known Socialist reformer, Robert Owen, and his disciples built that college—a fine edifice occupying a healthy position—and called it Harmony Hall, as it was meant to inaugurate the millennium; the letters “C. of M” (commencement of millennium) being inserted in flint in the brickwork of the house. Around this college were large farms, where lessons were given by Prof. Tyndall to the more advanced students on the subjects which he had mastered in his previous labours. With teaching he combined self-improvement. The chemical laboratory was under the charge of Dr. Frankland, with whom he soon became friendly. In order to spend part of his time in study in the chemical laboratory, Tyndall relinquished part of his salary, and there he laid the foundations of that knowledge of physical science which was destined afterward to be his own passport to fame and to afford delight to many thousands of his fellowmen. He was also very successful as a teacher in Queenswood College. He is said to have exercised a kind of magnetic influence over his students, and such was their faith in him that when any disturbances arose among them he was invariably called upon to settle them, and he did so merely by the power of moral influence and force of character. As to his impressions of life at Queenswood, the Professor says:—
“Schemes like Harmony Hall look admirable upon paper; but, inasmuch as they are formed with reference to an ideal humanity, they go to pieces when brought into collision with the real one. At Queenswood, I learned, by practical experience, that two factors went to the formation of a teacher. In regard to knowledge he must, of course, be master of his work. But knowledge is not all. There might be knowledge without power—the ability to inform without the ability to stimulate. Both go together in the true teacher. A power of character must underlie and enforce the work of the intellect. There were men who could so rouse and energise their pupils—so call forth their strength and the pleasure of its exercise—as to make the hardest work agreeable. Without this power it is questionable whether the teacher could ever really enjoy his vocation—with it, I do not know a higher, nobler, and more blessed calling than that of the man who, scorning the cramming so prevalent in our day, converts the knowledge he imparts into a lever, to lift, exercise, and strengthen the growing minds committed to his care.”
After pursuing their scientific studies together for some time, both Tyndall and Frankland began to think of extending the range of their scientific culture. But that could not then be done in England. In 1845 a man could not easily get first-class instruction in practical chemistry and the other physical sciences that were then making great strides forward. Between 1840 and 1850 Germany assumed the lead in these sciences. In that country science then organised itself on a vast scale, and from that time to this it has been growing there at a most extraordinary rate; indeed, Prof. Huxley declared in 1884 that in the whole history of the world there has never been such a tremendous amount of organised energy bestowed in the development of physical science as in Germany.
“At the time here referred to,” says Professor Tyndall, “I had emerged from some years of hard labour the fortunate possessor of two or three hundred pounds. By selling my services in the dearest market during the railway madness the sum might, without dishonour, have been made a large one; but I respected ties which existed prior to the time when offers became lavish and temptation strong. I did not put my money in a napkin, but cherished the design of spending it in study at a German university. I had heard of German science, while Carlyle’s references to German philosophy and literature caused me to regard them as a kind of revelation from the gods. Accordingly, in the autumn of 1848, Frankland and I started for the land of universities, as Germany is often called. They are sown broadcast over the country, and can justly claim to be the source of an important portion of Germany’s present greatness.
“Our place of study was the town of Marburg, in Hesse-Cassel, and a very picturesque town Marburg is. It clambers pleasantly up the hillsides, and falls as pleasantly towards the Lahn. On a May day, when the orchards are in blossom, and the chestnuts clothed with their heavy foliage, Marburg is truly lovely. It is the same town in which my great namesake, when even poorer than myself, published his translation of the Bible. I lodged in the plainest manner in a street which perhaps bore an appropriate name while I dwelt there. It was called the Ketzerbach—the heretics’ brook—from a little historical rivulet running through it. I wished to keep myself clean and hardy, so I purchased a cask and had it cut in two by a carpenter. That cask, filled with spring-water over night, was placed in my small bedroom, and never during the years that I spent there, in winter or in summer, did the clock of the beautiful Elizabethekirche, which was close at hand, finish striking the hour of six in the morning before I was in my tub. For a good portion of the time I rose an hour and a-half earlier than this, working by lamp-light at the Differential Calculus when the world was slumbering around me. I risked this breach of my pursuits and this expenditure of my time and money, not because I had any definite prospect of material profit in view, but because I thought the cultivation of the intellect important; because, moreover, I loved my work, and entertained a sure and certain hope that armed with knowledge one can successfully fight one’s way through the world. I ought not to omit one additional motive by which I was upheld at the time here referred to—that was the sense of duty. Every young man of high aims must, I think, have a spice of this principle within him. There are sure to be hours in his life when his outlook will be dark, his work difficult, and his intellectual future uncertain. Over such periods, when the stimulus of success is absent, he must be carried by his sense of duty. It may not be so quick an incentive as glory, but it is a nobler one, and gives a tone to character which glory cannot impart. That unflinching devotion to work, without which no real eminence in science is now attainable, implies the writing at certain times of stern resolve upon the student’s character: ‘I work not because I like work, but because I ought to work.’ At Marburg my study was warmed by a large stove. At first I missed the gleam and sparkle from flame and ember, but I soon became accustomed to the obscure heat. At six in the morning a small milch-brod and a cup of tea were taken to me. The dinner hour was one, and for the first year or so I dined at an hotel. In those days living was cheap in Marburg. Dinner consisted of several courses, roast and boiled, and finished up with sweets and dessert. The cost was a pound a month, or about eightpence per dinner. I usually limited myself to one course, using even that in moderation, being convinced that eating too much was quite as sinful, and almost as ruinous, as drinking too much. By attending to such things I was able to work without weariness for sixteen hours a day. My going to Germany had been opposed by some of my friends as quixotic, and my life there might, perhaps, be not unfairly thus described. I did not work for money; I was not even spurred by ‘the last infirmity of noble minds.’ I had been reading Fichte, and Emerson, and Carlyle, and had been infected by the spirit of these great men, the Alpha and Omega of whose teaching was loyalty to duty. Higher knowledge and greater strength were within reach of the man who unflinchingly enacted his best insight.”
Even a statue was capable of impressing this truth upon him. But it was the statue of the man who said of his own features: “This is the face of a man who has struggled energetically”—the man of whose portrait Carlyle says: “Reader, to thee thyself, even now, he has one counsel to give, the secret of his whole poetic alchemy. Think of living! Thy life, were thou the pitifullest of all the sons of earth, is no idle dream, but a solemn reality. It is thy own; it is all thou hast to front eternity with. Work, then, even as he has done and does—Like a star, unhasting yet unresting.” Equally impressive was the effect produced on Professor Tyndall by even the sight of the form of such a man. Finding himself one fine summer evening standing beside a statue of Goethe in a German city, the contemplation of this work of art, which he considered the most suitable memorial for a great man, excited a motive force within his mind, which he thought no purely material influence could generate. “There was then,” he says, “labour before me of the most arduous kind. There were formidable practical difficulties to be overcome, and very small means wherewith to overcome them; and yet I felt that no material means could, as regards the task I had undertaken, plant within me a resolve comparable with that which the contemplation of this statue of Goethe was able to arouse.”
From his youth Tyndall appeared to have a remarkable power, not only of attracting friends, but of retaining them. The circumstances under which he early became acquainted with his life-long friends, General Wynne and Professor Hirst, have already been mentioned. Hirst was scarcely sixteen years of age when he became acquainted with Tyndall, who was ten years older. Though they stood in the relation of pupil and teacher, their intimacy ripened into an enduring friendship which separation heightened rather than dissolved. An incident that occurred while Tyndall was studying at Marburg affords honourable evidence of this fact. The death of a relative in 1849 made Hirst the possessor of a small patrimony, which he determined to divide between himself and his former teacher. He accordingly pressed Professor Tyndall to accept one half of his small fortune, but much to his disappointment Tyndall would have none of it. Entreaties to accept it for friendship’s sake were unavailing, but friendship, like necessity, can invent strange means for attaining its end. Hirst took counsel with a German banker as to a way of conveying the money to his friend, and soon a device was carried out, by means of which the devotee of science had to sacrifice his self-denial on the altar of friendship. While at work one morning in his lodgings in Marburg the postman brought him a heavy roll closely packed and sealed, which, to his astonishment, contained all sorts of German coins amounting to 20l. sterling, a considerable gratuity for a student to receive in those days. He had no alternative but to accept it. On a subsequent occasion when Tyndall left Marburg to visit England another friend of his youth, General Wynne, offered to replenish his exchequer, which he feared must be nearly empty, but the offer was declined with assurances that such generous assistance was unnecessary.
CHAPTER II.
“No man ever yet made great discoveries in Science who was not impelled by an abstracted love.”—Sir Humphry Davy.
At the time when Professor Tyndall was studying at Marburg University, the principal figure there was Bunsen, who had been appointed Professor of Chemistry in 1838. He was a profound chemist, and his fame as a lecturer was so eminent as to attract many foreign students. A prolific discoverer, and peculiarly happy in his manner of demonstrating his scientific teaching, he soon fascinated the ardent minds of the two students from Queenswood. For two years Tyndall attended his chemical lectures. Indeed he learned German chiefly by listening to Bunsen. He has himself stated that Bunsen treated him like a brother, giving his time, space, and appliances, for the benefit of his studies. The subject which most attracted Tyndall’s attention was electro-chemistry, upon which Bunsen delivered an admirable course of lectures in 1848. The whole principle of the voltaic pile was thus explained to him in a masterful manner. He also made himself acquainted with chemical analyses, both quantitative and qualitative. He displayed no less zeal in the study of mathematics. For a considerable period he got private lessons from Professor Stegmann, under whose tuition he worked through analytical geometry of two and three dimensions, the Differential and Integral Calculus, and part of the Calculus of Variations.
His first scientific paper was a mathematical essay on screw surfaces, respecting which he says:—“Professor Stegmann gave me the subject of my dissertation when I took my degree: its title in English was, ‘On a Screw Surface with Inclined Generatrix, and on the Conditions of Equilibrium on such Surfaces.’ I resolved that if I could not, without the slightest aid accomplish the work from beginning to end it should not be accomplished at all. Wandering among the pine wood and pondering the subject, I became more and more master of it; and when my dissertation was handed in to the Philosophical Faculty it did not contain a thought that was not my own.”
But the man whose acquaintance at Marburg appeared to exercise most influence over his career was Dr. Knoblauch, who had just come thither from Berlin as extraordinary Professor of Physics, and who had already distinguished himself by his researches in radiant heat. He illustrated his lectures with a choice collection of apparatus brought from Berlin; and he not only suggested to Tyndall an exhaustive series of experiments bearing on a newly-discovered principle of physics, but supplied him with the necessary apparatus, and placed his own cabinet at his disposal for that purpose. The subject of investigation was diamagnetism.
Faraday’s discoveries and experiments in magnetism were then attracting the attention of the scientific world. He had shown in 1830 that by moving a magnet within the hollow of a coil of copper wire an electrical current was produced in the wire. This was a startling and pregnant discovery. Taking six hundred feet of insulated copper wire and winding it into a large vertical coil, he arranged the two ends of the wire into a small coil a little distance away from the large coil, and immediately above this small coil he suspended a balanced compass needle by a silk thread. Then, on dropping a bar magnet, or piece of iron magnetised, into the large coil, the needle, which was pointing towards the North Pole, instantly swung round, evidently impelled by magnetic force; when, again, the bar magnet was raised out of the hollow of the large coil, the needle moved round in the opposite direction; while it remained motionless so long as the bar magnet was at rest either inside or outside the coil. It thus appeared that an electrical current could be produced by the movement of the bar magnet—by dropping it into the coil or taking it out; and the current so produced he called an induced current. This operation is called magneto-electric induction. In 1845 Faraday greatly extended his magnetic discoveries. He not only established the magnetic condition of all matter by showing that every known body or thing could be influenced by magnetism, but he discovered a new property of magnetism, which he called diamagnetism. This was considered his greatest discovery.
By suspending bodies of an elongated form between the ends or poles of powerful magnets, he found that every substance was attracted or repelled from the magnetic poles; and he divided all bodies into two great classes, called magnetic and diamagnetic. The way in which a piece of iron is attracted by the poles or ends of a horseshoe magnet is a familiar illustration of the action of magnetic bodies, and the position that such bodies assume, pointing in a line from one pole to the other, he termed axial. On the other hand, diamagnetic bodies were those which, when freely suspended within the influence of the magnet, assumed a position at right angles to the line joining the poles of a magnet, or to the magnetic meridian; in other words, magnetic bodies pointed axially from pole to pole, or north and south; while diamagnetic bodies pointed east and west, or in an equatorial direction. Bismuth is a conspicuous example of diamagnetic substances. Scientific curiosity soon became excited as to the exact nature of the diamagnetic force in relation to crystals, some of which behaved in a mysterious manner between the poles of a magnet. Professor Plücker, of Bonn, discovered that some crystals formed of diamagnetic substances were not subject to the diamagnetic force; and to account for this he attributed to crystals an optical axis, upon which the poles of a magnet exercised a peculiar force. Plücker brought this theory before the British Association in 1848, and called it a new magnetic action. At the close of the same year, Faraday told the Royal Society that he had often been embarrassed by the anomalous magnetic results given by small cylinders of bismuth, and after investigation he referred these effects to the crystalline condition of the bismuth. In concluding his lecture on this subject, Faraday said:—“How rapidly the knowledge of molecular forces grows upon us, and how strikingly every investigation tends to develop more and more their importance, and their extreme attraction as an object of study. A few years ago, magnetism was to us an occult power affecting only a few bodies: now it is found to influence all bodies, and to possess the most intimate relations with electricity, heat, chemical action, light, crystallisation, and, through it, with the forces concerned in cohesion.” He thought there was in crystals a directive impelling force distinct from the magnetic and diamagnetic force.
Frequent conversations on this subject took place between Knoblauch and Tyndall in Germany during 1849. Knoblauch suggested that Tyndall should repeat the experiments of Plücker and Faraday; and as this operation was proceeding they agreed to make a joint inquiry into the deportment of crystals under the diamagnetic force. They laboured long at the problem before attaining any encouraging success. They examined the optical properties of crystals as well as made magnetic experiments with them, a great many experiments being made without discovering any new fact. Eventually, however, they found that various crystals did not act in accordance with the principles enunciated by Plücker, and the more they worked at the subject the more clearly it appeared that the deportment of certain bodies under the influence of magnetism was due, not to the presence of some force previously unknown, but to the crystalline structure of the substance under investigation, or as Tyndall put it, to peculiarities of material aggregation. For example, he showed that while a bar of iron attracted by a magnet sets itself in a line from pole to pole, an iron bar made of an aggregate of small bars sets itself in the opposite direction. Tyndall showed that the cause of the latter bar assuming an equatorial position was simply its mechanical structure, the small plates composing the “aggregated” bar setting from pole to pole. He found that the same law regulated the magnetic deportment of crystals, whose mechanism or structure, however, was generally less evident.
In 1849 eminent natural philosophers were studying this subject in England, France, and Germany, and it was expected that the investigation of diamagnetic phenomena would rapidly throw some new light upon the molecular forces which determine the conditions of the material creation. In allusion to this expectation, Tyndall said in 1850, that as nature acts by general laws, to which the terms great and small are unknown, it cannot be doubted that the modifications of magnetic force, exhibited by bits of copperas and sugar in the magnetic field, display themselves on a large scale in the crust of the earth itself, and as a lump of stratified grit, though a magnetic material, could be made, on account of its planes of stratification, to act as if it were diamagnetic, he suggested that this element might have some influence in determining the varying position of the magnetic poles of the earth—a subject which still perplexes the scientific world. Not only has the north magnetic pole gradually been changing its position, as shown by the records of three centuries, but, according to Barlow, every place has a magnetic pole and equator of its own; and according to Faraday the earth is a great magnet, whose power, as estimated by Gauss, is equal to that which would be conferred if every cubic yard of it contained six one-pound magnets; the sum of the force being thus equal to 8,464,000,000,000,000,000,000 such magnets. “The disposition of this magnetic force is not regular,” said Faraday, “nor are there any points on the surface which can be properly called poles: still the regions of polarity are in high north and south latitudes; and these are connected by lines of magnetic force (being the lines of direction), which, generally speaking, rise out of the earth in one (magnetic) hemisphere, and passing in various directions over the equatorial regions into the other hemisphere, there enter into the earth to complete the known circuit of power.”
It was in connection with his investigations on this subject that Prof. Tyndall first saw Prof. Faraday. Returning from Marburg in 1850, he called at the Royal Institution and sent in his card, together with a copy of a paper he had prepared, giving the results of his experiments on magne-crystallic action. Prof. Faraday conversed with him for half-an-hour, and being then on the point of publishing one of his papers on magne-crystallic action, he appended to it a flattering reference to the notes which Tyndall had placed in his hands.
Tyndall went back to Germany, where he worked for another year. In the beginning of 1851 he went to Berlin, where, he says, Prof. Magnus had made his name famous by physical researches of all kinds. “On April 28th, 1851, I first saw this Professor on his own doorstep in Berlin. His aspect won my immediate regard, which was strengthened to affection by our subsequent intercourse. He gave me a working place in his laboratory, and it was there I carried out my investigations on diamagnetism and magnecrystallic action published in the Philosophical Magazine for September, 1851. Among the other eminent scientific men whom I met at Berlin was Ehrenberg, with whom I had various conversations on microscopic organisms. I also made the acquaintance of Riess, the foremost exponent of frictional electricity, who more than once opposed to Faraday’s radicalism his own conservatism as regarded electric theory. Du Bois-Reymond was there at the time, full of power, both physical and mental. His fame had been everywhere noised abroad in connection with his researches on animal electricity. Du Bois-Reymond became perpetual secretary to the Academy of Sciences, Berlin. From Professor Magnus, and from Clausius, Wiedemann, and Poggendorff, I received every mark of kindness, and formed with some of them enduring friendships. Helmholtz was at this time in Königsberg. He had written his renowned essay on the “Conservation of Energy,” which I afterward translated. Helmholtz had, too, just finished his experiments on the velocity of nervous transmission, proving this velocity, which had previously been regarded as instantaneous, or, at all events, as equal to that of electricity, to be, in the nerves of the frog, only 93 ft. a second, or about one-twelfth of the velocity of sound in air of the ordinary temperature. In his own house I had the honour of an interview with Humboldt. He rallied me on having contracted the habit of smoking in Germany, his knowledge on this head being derived from my little paper on a water-jet, where the noise produced by the rupture of a film between the wet lips of a smoker is referred to. He gave me various messages to Faraday, declaring his belief that he (Faraday) had referred the annual and diurnal variation of the declination of the magnetic needle to their true cause—the variation of the magnetic condition of the oxygen of the atmosphere. I was interested to learn from Humboldt himself that, though so large a portion of his life had been spent in France, he never published a French essay without having it first revised by a Frenchman. In those days I not unfrequently found it necessary to subject myself to a process which I called depolarisation. My brain, intent on its subjects, used to acquire a set, resembling the rigid polarity of a steel magnet. It lost the pliancy needful for free conversation, and to recover this I used to walk occasionally to Charlottenburg or elsewhere. From my experiences at that time I derived the notion that hard thinking and fleet talking do not run together.”
Prof. Tyndall was exceptionally fortunate in getting so easily and so early into the friendship of such eminent men of science. In those days to form such eminent acquaintances was no small achievement for a young Irishman; but on the other hand, he had fully earned this distinction by the vigour and originality with which he attacked the latest and most perplexing problem of that time. During the five years that had elapsed since Faraday discovered diamagnetism, the subject had been investigated by the greatest scientists in England, France, and Germany, and no one had done so much to elucidate it as Prof. Tyndall. In order to master that subject he began in November, 1850, an investigation of the laws of magnetic attractions. The laws of magnetic action at distances in comparison with which the thickness of the magnet vanishes, had long been known, but the laws of magnetic action at short distances, where the thickness of the magnet comes fully into play, had not previously been subjected to reliable experiments, and were therefore at that time a perplexing matter of speculation. That desideratum he now supplied. He found, among other things, that the mutual attraction of a magnet and a sphere of soft iron, when both are separated by a small fixed distance, is directly proportional to the square of the strength of the magnet, and that the mutual attraction of a magnet of constant strength and a sphere of soft iron is inversely proportional to the distance between them.
Next year (1851) he published the results of further investigations into the relations between magnetism and diamagnetism. He found that the laws which govern magnetism and diamagnetism are identical, that the superior attraction or repulsion of a mass in any particular direction is due to the direction in which the material particles are arranged most closely together, that the forces exerted are attractive or repulsive according as the particles are magnetic or diamagnetic, and that this law is applicable to matter in general.
A paper on “The Polarity of Bismuth,” which might be regarded as a temporary instalment of his diamagnetic researches, ended with the remark that during this inquiry he had changed his mind too often to be over-confident now in the conclusion at which he had arrived. Part of the time he was a hearty subscriber to the opinion of Faraday that there existed no proof of diamagnetic polarity; and if, he said, “I now differ from that great man, it is with an honest wish to be set right, if through any unconscious bias of my own I have been led either into errors of reasoning or mis-statements of fact.”
The theory of diamagnetism was still an apple of discord in the scientific world; and although Prof. Tyndall used the language of deference rather than of doubt, he did not allow the subject to remain in a state of uncertainty. He continued his researches in Berlin, in the private laboratory of Prof. Magnus, who afforded him every possible facility for carrying on experiments, and took a lively interest in the investigation. The result was the confirmation of his previous impression that the action of crystals within the range of a magnet’s influence (technically called the “magnetic field”) was due to peculiarities of molecular arrangement. He found, for example, that a crystal of carbonate of iron, which, when suspended in the magnetic field, showed a certain deportment, could be pounded into the finest dust, and the particles could be so put together again that the mass would exhibit the same deportment as before.
Dr. Bence Jones, the Secretary of the Royal Institution, who had heard of Tyndall in Berlin in 1851, afterwards invited him to give a Friday evening lecture at the Royal Institution. “I went,” he says, “not without fear and trembling, for the Royal Institution was to me a kind of dragon’s den, where tact and strength would be necessary to save me from destruction.” The lecture, which was delivered on February 11th, 1853, was “On the Influence of Material Aggregation upon the Manifestations of Force,” and it gave a beautiful and simple exposition of the principles of magnetic and diamagnetic action discovered by himself, the chief being that the line of greatest density is that of strongest magnetic power. In the course of his lecture he pointed out that anything which increases density increases magnetic power; and upon that principle he contended that the local action of the sun upon the earth’s crust must influence in some degree the diurnal range of the magnetic needle, which Faraday, on the other hand, attributed to the modification of our atmosphere by the sun’s rays. While thus endeavouring to upset Faraday’s theory, he concluded by saying: “This evening’s discourse is, in some measure, connected with this locality, and thinking thus, I am led to inquire wherein the true value of a scientific discovery consists? Not in its immediate results alone, but in the prospect which it opens to intellectual activity, in the hopes which it excites, in the vigour which it awakens. The discovery which led to the results brought before you to-night was of this character. That magnet was the physical birthplace of these results; and if they possess any value they are to be regarded as the returning crumbs of that bread which in 1846 was cast so liberally upon the waters. I rejoice in the opportunity here afforded me of offering my tribute to the greatest worker of the age, and of laying some of the blossoms of that prolific tree which he planted at the feet of the great discoverer of diamagnetism.” At the conclusion of the lecture Faraday quitted his usual seat, and crossing the theatre to the corner where the lecturer stood, cordially shook him by the hand and congratulated him on his success. A second lecture was delivered by him on June 3rd, 1853, “On some of the Eruptive Phenomena of Iceland,” and a month later he was unanimously elected Professor of Natural Philosophy in the Royal Institution.
Some years previously he had read in a serial publication an account of Davy’s experiments on radiant heat at the Royal Institution, and he remembered ever after the longing then excited in him to be able to do something of the same kind. Now he was to occupy a position in which he should use, in his own lectures, the same apparatus of which illustrations were given in the magazine article that had fired his youthful ambition. To that position he was promoted on the recommendation of Faraday, and respecting his appointment he himself said: “I was tempted at the time to go elsewhere, but a strong attraction drew me here. It was his (Faraday’s) friendship that caused me to value my position here more highly than any other.”
While the controversy respecting magnetic and diamagnetic hypotheses was still raging, Faraday delivered a lecture at the Royal Institution early in 1855 with the express object of cautioning the investigators of scientific truths against placing too much confidence on any hypothesis. He stated that every year of increased experience had taught him more and more to distrust the theories he had once adhered to; and his present impression with regard to existing Magnetic and Electrical hypotheses was, that they were very unsatisfactory, and that the propounders of them had been following in a wrong track. As an instance of the obstacles which erroneous hypotheses throw in the way of scientific discovery, he mentioned the unsuccessful attempts that had been made in this country to educe magnetism from electricity, until Oersted showed the simple way. He said that the identity of magnetism and electricity had been strongly impressed upon the minds of all: when he came to the Royal Institution, as an assistant in the laboratory, he saw Davy, Wollaston, and Young trying by every way that suggested itself to them to produce magnetic effects from an electric current; but, having their minds diverted from the true course by their existing hypotheses, it did not occur to them to solve the point by holding a wire, through which an electric current was passing, over a suspended magnetic needle—the experiment by which Oersted afterwards proved, by the deflection of the needle, the magnetic property of an electric current.
Such cautions, however, did not deter Professor Tyndall from defending the position he had taken up with regard to magnetism and diamagnetism. He still maintained that the influence of structure was supremely important,—that under the influence of magnetism or electricity a normal diamagnetic bar always exhibits a deportment precisely antithetical to that of a normal magnetic bar; but that, by taking advantage of structure, it is possible to get diamagnetic bars which exhibit precisely the same deportment as normal magnetic ones, and magnetic bars which exhibit a deportment precisely similar to normal diamagnetic ones. He showed numerous experiments before the British Association in support of his contention that the diamagnetic force is a polar one, with a direction opposite to that of the force in ordinary magnetic bodies. Professor William Thomson, who witnessed the experiments, certified the success of every one of them; and stated that Professor Tyndall’s discoveries in this domain of science had cleared away a mass of rubbish and set things in their true light, adding that in many cases he had repeated and varied Tyndall’s experiments, and had found them to be true.
In 1855 he delivered the Bakerian lecture, in which he gave an elaborate account of his latest researches respecting the phenomena of diamagnetism. He was now firmly convinced, he said, that the force that repelled a body was similar in character to that which attracted a body; in other words, that diamagnetic bodies possess the same kind of polarity, but in the opposite direction to that of magnetic bodies. But the opponents of diamagnetic polarity, who were not yet satisfied by the evidence he adduced, said that his experiments were made with electrical conductors in which induced currents could be formed that might account for the attractions and repulsions. Professor Tyndall thought it would tend to settle the question if he were to use a new kind of apparatus that would obviate that objection. He therefore wrote to Professor Weber, of Göttingen, whom Professor William Thomson described at the time as the most profound and accurate of all experimenters, asking him to devise more delicate and powerful means than had hitherto been used in experimental tests. Weber not only devised a greatly improved apparatus, but had it constructed under his own superintendence at Leipsig.[2] With this apparatus Professor Tyndall was able to satisfy the severest conditions proposed by those who discredited the results of previous experiments. He then silenced doubt by demonstrating that magnetism and diamagnetism stand, in respect of polarity, on the same footing, with this difference, that the one polarity is the inversion of the other. This diamagnetic polarity, previously established in the case of bismuth, he showed to exist in slate, marble, calcspar, sulphur, &c. He also established the polarity of liquids, magnetic and diamagnetic. At the Royal Institution in February, 1856, he showed that prisms of the same heavy glass as that with which Faraday discovered the diamagnetic force, behaved under the magnet in the same way as bismuth; and this evidence was admitted to be conclusive by the opponents of diamagnetic polarity. The controversy thereafter subsided.
His chief papers recording his most important investigations in connection with diamagnetism were afterwards collected into a volume entitled Researches on Diamagnetism and Magnecrystallic Action.
In 1855 Professor Tyndall was appointed Examiner under the Council for Military Education, and an incident which occurred shortly afterwards illustrated the confidential relations into which his intimacy with Faraday had ripened, as well as the independence of character which distinguished both. Being strongly impressed with the advantage of increasing the knowledge of physical science given to artillery officers and engineers, Professor Tyndall advocated a more liberal recognition of scientific attainments in their examinations. At that time a committee of the British Association was endeavouring to get the British Government to recognise the claims of science; and in reply to inquiries made by that committee as to the expediency of offering inducements for the acquisition of science and of offering orders and decorations as rewards for proficiency, Professor Faraday said: “I cannot say that I have not valued such distinctions; on the contrary, I esteem them very highly; but I don’t think I have ever worked for, or sought after, them.” Lord Harrowby, in his address as President of the British Association, said that the State had till recently done absolutely nothing for the promotion of science; and it was remarked as a strange circumstance that though there were then in the Cabinet the President and President-elect of the British Association, it was considered too hazardous to apply to the Government for money for scientific purposes. While this neglect of science was being freely discussed a number of well-instructed young men were sent from Trinity College, Dublin, to compete at the Woolwich examinations in 1856 for appointments in the artillery and engineers, and their scientific knowledge appeared so creditable that Professor Tyndall thought it unnecessary to say anything about it. His colleagues, on the other hand, sent in as usual brief reports with their returns calling attention to the chief features of the examination, and a leader in the Times pointed out that the concurrent testimony of the examiners was that, both in mathematics and classics, the candidates showed a marked improvement, but that on other points they broke down. This appeared to Professor Tyndall an unjust reflection upon their scientific attainments, which were thus ignored. He accordingly wrote to the Times simply stating that “in justice to the candidates for commissions in the artillery and engineers examined by me in natural philosophy and chemistry, you will perhaps permit me to state that the general level of the answers in the last examination was much higher than that attained in the first; many of the papers returned to me gave evidence of rare ability, and if during their future career the authors of these papers continue to cultivate the powers which they have shown themselves to possess, they will, I doubt not, justify by their deeds the high opinion entertained of them.” This modest statement, intended to put the students right, put himself wrong. The Secretary of State for War promptly informed him that an examiner appointed by the Commander-in-Chief had no right to appear in the public papers as Professor Tyndall had done without the sanction of the War Office. To this reproof he at once wrote a firm but respectful reply, which, however, he submitted to Faraday before despatching it. Faraday pointed out that the consequence of sending such a reply would be dismissal. Professor Tyndall said he knew that, but he would not silently accept the reproof of the War Office. “Then send the reply,” said Faraday; and it was sent. Henceforth Professor Tyndall was in daily expectation of receiving his discharge. After a delay, the length of which surprised him, he received a reply, the contents of which still more surprised him. His explanation was “deemed perfectly satisfactory” by the Secretary for War, and he therefore continued for many years afterwards in the service of the Council for Military Education.
One of the next subjects that occupied his attention was the cleavage of slate rocks. It is a question of great importance in connection with geological problems, and hitherto only speculative solutions had been offered of what appeared to be one of the most mysterious but grandest operations of nature. For twenty years previously geologists were mostly content to accept on trust the suggestion of Professor Sedgwick, that crystalline forces had rearranged whole mountain masses so as to produce a beautiful crystalline cleavage. In 1854 Professor Tyndall visited the quarries of Cumberland and North Wales, where the question of cleavage came prominently before him. When at Penrhyn Quarry he was told that the planes of cleavage were the planes of stratification lifted up by some convulsion into an almost vertical position. But a little observation satisfied him that this view was essentially incorrect; for in certain masses of slate in which the strata were distinctly marked, the planes of cleavage were at a high angle to the planes of stratification. A little experiment, he said, demonstrated that the cleavage of slate was no more a crystalline cleavage than that of a hayrick. An elaborate examination of all the conditions of the phenomena led him to the conclusion that cleavage was the result of pressure, and that this effect of pressure was not confined to slates. In a lecture delivered in 1856 he stated that for the previous twelve months the subject had presented itself to him almost daily under one aspect or another. “I have never,” he said, “eaten a biscuit during this period in which an intellectual joy has not been superadded to the more sensual pleasure, for I have remarked in all such cases cleavage developed in the mass by the rolling-pin of the pastrycook or confectioner. I have only to break these cakes and to look at the fracture to see the laminated structure of the mass.” He exhibited some puff-paste baked under his own superintendence, and explained that while the cleavage of our hills was accidental, in the pastry it was intentional.
Among those who heard the lecture upon slaty cleavage was his friend Professor Huxley, who suggested that probably the principles then enunciated might account for the structure of glaciers, another subject that had long perplexed scientific observers. The greatest authority on glaciers at that time was Professor J. D. Forbes, of Edinburgh University, who in 1842 declared that a “glacier is an imperfect fluid or viscous body, which is urged down slopes of a certain inclination by the mutual pressure of its parts,” and who detected in glaciers a veined structure which he explained as fissures produced by particles of ice in motion sliding past each other, leaving the fissures to be filled with water and to be frozen in winter. On examining the published observations of Forbes, Professor Tyndall was struck with the probable accuracy of Professor Huxley’s suggestion, and in order to examine the matter more thoroughly, the two advocates of the cleavage theory arranged to visit together the glaciers of Grindelwald, the Aar, and the Rhone. This personal investigation and subsequent reflection confirmed Professor Tyndall in his views. He found that glaciers were formed by the property of ice which Faraday called regelation; that is, the freezing together of two pieces of ice by simple contact and slight pressure. It is the same property that enables boys to make snowballs and snow men when the snow is beginning to melt, or when the warmth of the hand raises its temperature to the point at which regelation takes place. Professor Tyndall found that when two confluent glaciers united to form a single trunk, their mutual pressure developed the veined structure in a striking degree along their line of junction. In his lectures on the subject at the Royal Institution he ingeniously illustrated the processes of Nature which make and unmake the glacier. To show that ice only becomes compressed into a solid mass at a temperature near that of freezing water, he cooled a mass of ice by exposing it to the action of the coldest freezing mixture then known. He then crushed this cooled mass of ice into fragments, and applied pressure to the fragments for the purpose of making them cohere, but they did not show the slightest cohesiveness. Very different was their action when their temperature was raised to the freezing point. When placed in a wooden cup and pressed by a hollow wooden die a size smaller than the cup, the pieces of ice became united into a compact cup of nearly transparent ice. Glaciers, he contended, were formed by a similar operation. As particles of snow or ice descend the mountain side, the pressure becomes sufficiently great to compress the particles into a mass of solid ice, which eventually assumes the magnitude of a beautiful glacier. He observed that in the laboratory of Nature it was exactly at the places where squeezing took place that the cleavage of the ice was most highly developed. In fact, he said, the association of pressure and lamination was far more distinct in the case of the glacier than in the case of the slate rock, and as it was now known that pressure caused the lamination of slate rock, he contended that it was the same cause that produced like effects in glaciers.
In a lecture delivered early in 1858, he gave an account of some beautiful phenomena of the glacier. In the preceding September and October he examined the effect of sending a beam of radiant heat through a mass of ice. When sunbeams condensed by a lens were sent through slabs of ice, the path of the beam was instantly studded with lustrous spots like brilliant stars, and “around each the ice was so liquefied as to form a beautiful flower-shaped figure, possessing six petals. From this number there was no deviation. At first the edges of the liquid leaves were clearly defined: but a continuance of the action usually caused the edges to become serrated like those of ferns. When the ice was caused to move across the beam, or the reverse, the sudden generation and crowding together of these liquid flowers, with their central spots shining with more than metallic brilliancy, was exceedingly beautiful.” By means of the electric light and a piece of ice prepared for the purpose he was able to exhibit these lovely ice-flowers to a delighted audience at the Royal Institution.
During the years 1857 and 1858 Professor Tyndall continued his observations of glacier phenomena amid the solitude of the Alps. In the summer of the latter year he betook himself to the mountains with the view of settling once for all “the rival claims of the only two theories, which then deserved serious attention, namely, those of pressure and of stratification.” Again his former views were completely confirmed. It is difficult, he said, to convey in words the force of the evidence which the glacier of Grindelwald presents to the mind of the observer who sees it; it looked like a grand laboratory experiment made by Nature herself with special reference to the point in question. The squeezing of the mass, its yielding to the force brought to bear upon it, its wrinkling and scaling off, and the appearance of the veins at the exact point where the pressure began to manifest itself, left no doubt on his mind that pressure and structure stood to each other in the relation of cause and effect.
The conclusions at which he arrived as to the structure and movement of glaciers brought him into collision with Professor Forbes, whose views, enunciated fifteen years previously, were then widely accepted as the most scientific exposition of the subject. Forbes seemed rather sensitive about his own theory, and complained that he had to some extent been misrepresented. But in the conflict of opinions Professor Tyndall invariably referred to Professor Forbes’s labours in connection with the subject in the most appreciative and complimentary language. For instance, in 1858 he said he would not content himself with saying that the book of Professor Forbes was the best that had been written upon the subject; “the qualities of mind, and the physical culture invested in that excellent work, were such as to make it, in the estimation of the physical investigator at least, outweigh all other books upon the subject taken together.” That is more generous language than Professor Forbes ever used respecting Professor Tyndall. In 1865, after the heat of controversy had been dissipated, Forbes wrote that “Dr. Tyndall’s so-called proofs that it is through ‘fracture and regelation’ that a glacier moulds itself to its bed are to my mind no proofs at all;” and that he regarded Mr. Hopkins’s mathematical demonstrations about glaciers as “irrelevant mathematical exercitations.” Nevertheless, Professor Tait, the friend and scientific biographer of Forbes, said in 1873: “To say that Forbes thoroughly explained the behaviour of glaciers would be an exaggeration; but he must be allowed the great credit of being the Copernicus or Kepler of this science.” As the subject still continues to exercise the intellect of the scientific explorers of the Alps, suffice it for the present to say that if time ratifies the position which Professor Tait has assigned to Professor Forbes, his greatest and boldest successor in the same field may be described as the Newton of glacier phenomena.
FOOTNOTES:
[2] The force of diamagnetism is vastly feebler than that of ordinary magnetism. According to Weber, the magnetism of a thin bar of iron exceeds the diamagnetism of an equal mass of bismuth about two and a-half million times.
CHAPTER III.
“Every secret which is disclosed, every discovery which is made, every new effort which is brought to view, serves to convince us of numberless more which remain concealed, and which we had before no suspicion of.... Knowledge is not our proper happiness. Whoever will in the least attend to the thing will see that it is the gaining, not the having of it, which is the entertainment of the mind.”—Bishop Butler.
Next, probably, to magnetism and electricity, the scientific investigation of the laws of heat has yielded the most fruitful and the most curious results. The science of heat made the greatest progress about the middle of the present century, and Professor Tyndall was one of its most successful investigators. Being a force co-related to electricity, it is scarcely remarkable that the same natural philosopher should reveal to us not a few of these silent operations of magnetism and heat that previously were unobserved or were regarded as mysteries.
When, in 1859, he turned his attention to the absorption of radiant heat by gases and vapours, there was considerable diversity of opinion as to the effect of the atmosphere on radiant heat; and great skill and patience were required in devising experiments, and in detecting and eliminating the various sources of error. Till then it was thought that the subject was outside the realm of experiment, but Professor Tyndall soon demonstrated that heat in gases and vapours was subject to various laws which had most important effects in every part of the world. In his first memoir he established not only the existence of absorption and radiation in gases, but that the differences of absorption and radiation were as great among gases as among liquids and solids. He showed that the elementary gases, hydrogen, oxygen, nitrogen, as well as air freed from moisture and carbonic acid, examined in a length of four feet, absorb about 3½ per cent. of heat radiated from lamp-black at 212°, the slightest impurity in the gas, however, altering the rate of absorption. With compound gases and vapours very different results were obtained. About twenty gases and vapours were examined, and it was found that while the elementary gases already named gave the feeblest action, olephiant gas showed the most energetic action, absorbing 81 per cent. He also made the important discovery that by arranging the various gases in order according to their power, first of radiating heat and then of absorbing radiant heat, the order was the same in both cases; in short, the order of radiation was exactly that of absorption. In his second memoir he introduced a new and remarkable method of determining absorption and radiation. This method he called “dynamic radiation.” Dispensing with the use of any extraneous source of heat, he obtained his results by the heat or cold produced by the condensation or rarefication of the gases. Just as a ball striking a target is heated by collision, so he heated gas contained in one part of a tube by the collision of its particles against the surface of another part into which they rushed to fill a vacuum. He found, he said, by strict experiments that the dynamic radiation of an amount of boracic ether vapour, possessing a tension of only one 1,012,500,000th of an atmosphere, was easily measurable.
His researches on the relation of radiant heat to aqueous vapour, published in 1863, were the most interesting and useful. Such were the difficulties connected with the investigation of this part of the subject that Professor Tyndall and his old friend Professor Magnus, of Berlin, arrived at and long maintained opposite conclusions as to the absorption of radiant heat by the air and the influence of aqueous vapour. Early in his researches Professor Tyndall regarded the action of the atmosphere as a particular part of his inquiry, and, accordingly, his third memoir was specially devoted to the radiation of aqueous vapour. The conclusion he came to was that the aqueous vapour in our atmosphere intercepted or absorbed eighty times more heat than the air, and as there was only one atom of aqueous vapour for every 200 of oxygen and nitrogen composing the air, it appeared that one atom of the former absorbed 16,000 times more than one atom of oxygen or nitrogen. This startling conclusion he verified by a system of checks and counter-checks which were considered as decisive. The applications of this discovery were manifold and important. The aqueous vapour which absorbed so much heat he likened to a blanket which is more necessary to the vegetable life of England than clothing is to man. “Remove for a single summer night,” he said, “the aqueous vapour from the air which overspreads this country, and you would assuredly destroy every plant capable of being destroyed by a freezing temperature. The warmth of our fields and gardens would pour itself unrequited into space, and the sun would rise upon an island held fast in the iron grip of frost.” The aqueous vapour constitutes a local dam, which deepens the temperature at the earth’s surface, but which finally overflows and gives to space all that we receive from the sun. This discovery presented an explanation of some phenomena, which hitherto had been imperfectly understood. It was evidently the absence of this aqueous screen which made the winters in Central Asia almost unendurable; and it showed how the burning heat of the Sahara during the day was followed by intense cold at night.
Before Professor Tyndall had published all his observations on the relations between radiant heat and aqueous vapour, his friend, Professor Frankland, regarded them as sufficient to account for the glacial era, and the action of glaciers over the entire globe. During a visit to Norway in 1863 Frankland considered the subject afresh, and came to the conclusion that the chief cause of the phenomena of the glacial epoch was a higher temperature of the ocean than prevails at present. The critics of the day pointed out that such a view depended upon the accuracy of the assumption that our earth had gradually cooled down from an originally incandescent state; and it is now generally admitted by natural philosophers that the earth has cooled down from a state of liquid heat. In that case the waters of the ocean, when cooling down from the boiling point, would be at a higher temperature than the present; and Professor Frankland maintained that it was in the later stages of the cooling process that the glacial epoch occurred. The great natural glacial apparatus he divided into three parts—the evaporator, the condenser, and the receiver. The cooling ocean was the evaporator; the mountains were the icebearers or receivers; while the dry air which permitted the heat from the vapour to radiate into space, acted as the condenser. He made numerous experiments to show that under these conditions the land would cool more rapidly than the sea; and he maintained that in the glacial epoch the “rays of heat streamed into space from the ice-bearing surfaces with comparatively little interruption, whilst the radiation from the sea was as effectually retarded as if the latter had been protected with a thick envelope of non-conducting material. Thus, whilst the ocean retained a temperature considerably higher than at present, the icebearers had undergone a considerably greater refrigeration.” He calculated that an increase of 20° in the temperature of the coast of Norway would double the evaporation from a given surface, and such an increased evaporation, accompanied of course by a corresponding precipitation, “would suffice to supply the higher portions of the land with that gigantic ice-burden which ground down the mountain slopes during the glacial epoch.” Such a view did not require the assumption of any natural convulsion or catastrophe; on the contrary it accounted for the glacial epoch by the evolution of thermal conditions, the existence of which is now generally admitted.[3]
In his fourth memoir, published in 1864, “On the Radiation and Absorption of Heat by Gaseous and Liquid Matter,” Professor Tyndall showed that generally the absorption of non-luminous radiant heat by vapours was the same as that of the liquids from which the vapours were produced.
His fifth memoir, entitled “Contributions to Molecular Physics,” was made the Bakerian lecture for that year. In it he deduced from numerous experiments the remarkable law that the opacity of a substance with respect to radiant heat from a source of comparatively low temperature increases with the chemical complexity of its molecule. He examined the effects of temperature on the transmission of radiant heat, the radiation from flames of various kinds, and the influence of vibrating periods on the absorption of radiant heat.
In November, 1864, the Royal Society presented him with the Rumford medal for his researches on the absorption and radiation of heat by gases and vapours; and General Sabine, in making the presentation, said such had been the fate of Professor Tyndall that each last achievement might almost be said to have dimmed the lustre of those which preceded it. Curiously enough his very next achievements thereafter did dim the lustre of those published prior to the presentation of the Rumford Medal. It was the discovery of a means of separating light from heat. Melloni had previously discovered a combination of screens by which radiant heat could be arrested or separated from light, an operation which is effected on a vast scale by the moon when it reflects the light of the sun. Professor Tyndall effected the converse operation. He discovered that a solution of iodine in bisulphide of carbon entirely intercepted the light of the most brilliant flames. A hollow prism filled with that opaque liquid and placed in the path of the beam from an electric lamp, completely intercepted the light, but transmitted the heat unimpaired. In this way he succeeded in separating with marvellous sharpness the invisible from the visible radiations of the lime light, the electric light, and the sun. He not only produced combustion, fusion, and incandescence by invisible radiation, but he proved that in the case of the electric light the invisible rays are no less than eight times as powerful as the visible radiations. He obtained all the colours of the solar spectrum from a platinum foil raised to incandescence at the invisible focus; and this rendering of a refractory body incandescent by invisible rays he called calorescence. In connection with these investigations he performed a daring experiment. Knowing that a layer of iodine placed before the eye intercepted the light, he determined to place his own eye in the focus of strong invisible rays. He knew that if in doing so the dark rays were absorbed in a high degree by the humours of the eye, the albumen of the humours might coagulate; and on the other hand, if there was no high absorption, the rays might strike upon the retina with a force sufficient to destroy it. When he first brought his eye, undefended, near the dark focus, the heat on the parts surrounding the pupil was too intense to be endured. He therefore made an aperture in a plate of metal, and placing his eye behind this aperture, he gradually approached the point of convergence of the invisible rays. First the pupil and next the retina were placed in the focus without any sensible damage. Immediately afterwards a sheet of platinum foil placed in the position which the retina had occupied became red-hot.
In a subsequent memoir he dealt with the influence of colour and mechanical condition upon radiant heat, demonstrating that white bodies are far more potent absorbers of radiant heat than black ones.
During the first thirteen years of his researches in the laboratory of the Royal Institution he produced thirteen papers, which were published in the Philosophical Transactions. Conspicuous among these were his papers on the radiation and absorption of heat, and his researches on that subject have generally been admitted to be of the most thorough and original character. A lucid epitome of the chief results he obtained was given in the Rede lecture which he delivered before the University of Cambridge in 1865, when the University conferred on him the honorary degree of LL.D.
In 1863 he published the first edition of one of his most popular books, Heat Considered as a Mode of Motion—a book which an eminent electrician has recommended students of electricity to master; in 1867 he published a volume of lectures on “Sound”; and in 1869-74 he published his lectures on “Light.” These works have gone through several editions. As an illustration of the interest with which he can invest such impalpable subjects, it is worth remarking that a Chinese official, named Hsii-chung-hu, was so pleased with the book on Sound that he had it translated into the Chinese language and printed at Shanghai, in order that his countrymen might participate in the pleasure and instruction which he had derived from it. It was published at the expense of the Chinese Government, and sold at 1s. 6d. a copy.
During the ten years from 1859 to 1869, says Professor Tyndall, “researches on radiant heat in its relations to the gaseous form of matter occupied my continual attention.” But towards the close of that period his main inquiry, as it extended into space, began to spread out into various branches. In 1866 he entered upon an examination of the chemical action of light upon vapours, and the action of heat of high refrangibility as an explorer of the molecular condition of matter. “In this investigation one obstacle to be overcome was the presence of the floating matter in the air. The processes for the removal of these particles became the occasion of an independent research, branching out into various channels: on the one hand, it dealt with the practical problem of the preservation of life among firemen exposed to heated smoke; and, on the other, it approached the recondite question of spontaneous generation. He subjected the compound vapours of various substances to the action of a concentrated beam of light. The vapours were decomposed, and non-volatile products were formed. The decompositions always began with a blue cloud, which discharged perfectly polarised light at right angles to the beam. This suggested to him the origin of the blue colour of the sky; and as it showed the extraordinary amount of light that may be scattered by cloudy matter of extreme tenuity, he considered that it might be regarded as a suggestion towards explaining the nature of a comet’s tail.”
Regions of cloud and smoke are proverbial as symbols of the negation of human interest; but Professor Tyndall imparted new beauties to the one and deprived the other of its terrors. He said to the chaotic vapours “Light,” and that which was without form and void instantly assumed the loveliest forms that Nature knows. Incredible as this language may appear to some, it is no mere Oriental hyperbole. He made the light from an electric lamp to pass through a great glass tube containing transparent, invisible vapours, and the action of the light at once commencing chemical decomposition, various cloud forms resembling organic structures were seen in the tube. The following is the beautiful description he gave to the Royal Society of the phenomena presented by hydriodic acid:—
“The cloud extended for about eighteen inches along the tube, and gradually shifted its position from the end nearest the lamp to the most distant end. The portion quitted by the cloud proper was filled by an amorphous haze, the decomposition, which was progressing lower down, being here apparently complete. A spectral cone turned its apex towards the distant end of the tube, and from its circular base filmy drapery seemed to fall. Placed on the base of the cone was an exquisite vase, from the interior of which sprang another vase of similar shape; over the edges of these vases fell the faintest clouds, resembling spectral sheets of liquid. From the centre of the upper vase a straight cord of cloud passed for some distance along the axis of the experimental tube, and at each end of this cord two involved and highly iridescent vortices were generated. The frontal portion of the cloud which the cord penetrated assumed in succession the form of roses, tulips, and sunflowers. It also passed through the appearance of a series of beautifully-shaped bottles placed one within the other. Once it presented the shape of a fish, with eyes, gills, and feelers.”
In 1869 it was stated before the British Association that M. Morren, while living in the South of France, had succeeded in producing similar results by the use of sunlight instead of the electric light.
For a long time during his researches on the decomposition of vapours he was troubled by the presence of floating matter revealed by a powerful condensed beam of light, and he tried numerous expedients for the purpose of intercepting this matter. At last he succeeded. By causing the air intended for experimental purposes to pass over the tip of a spirit-lamp flame, the floating matter disappeared. He therefore concluded that it was organic matter, which had been burned out by the flame. This discovery took place on October 5th, 1868. Till then he regarded the dust of our air as for the most part inorganic and noncombustible. This led him on to the investigation of the germ theory. On the one hand he added proof to proof, and experiment to experiment, to show that when a consuming heat was applied to air its organic matter disappeared; and on the other hand he maintained that as surely as a fig comes from a fig, a grape from a grape, and a thorn from a thorn, so surely does the typhoid virus or seed, when planted or scattered about among people, increase and multiply into typhoid fever, scarlatina virus into scarlatina, and small-pox virus into small-pox. These conclusions formed the subject of a famous lecture on “Dust and Disease,” delivered at the Royal Institution on January 21st, 1870. Among his audience were some of the foremost men of the day, such as Mr. W. E. Gladstone, then Prime Minister, Earl Granville, Dean Stanley, Sir Edwin Landseer, Sir Henry Holland, and Professor Huxley. The views which Professor Tyndall then put forth were received with marked disfavour among the medical profession. Even scientific men did not hesitate to pour ridicule upon the germ theory. For example, Professor Bloxam, Lecturer on Chemistry to the Department of Artillery Studies, suggested in one of his lectures that the Committee on Explosives should abandon gun cotton, and collecting the germs of small-pox and similar malignant diseases in cotton or other dust-collecting substances, should load shells with them, and we should then hear of the enemy being dislodged from his position by a volley of typhus or a few rounds of Asiatic cholera. Like most truths, the germ theory survived the ridicule of its opponents.
The labours of Pasteur in relation to the germ theory always appeared to command Professor Tyndall’s admiration. A large part of his lecture on “Dust and Disease” consisted of an account of the successful way in which Pasteur dealt with the epidemic among silkworms in France. Writing in April, 1870, the Professor said: “There is more solid science in one paper of Pasteur than in all the volumes and essays that have been written against him. Schroeder and Pasteur have demonstrated that air filtered through cotton-wool is deprived wholly, or in part, of its power to produce animalcular life. Why? An experiment with a beam of light answers the question; for while it proves our ordinary air to be charged with floating matter, the beam pronounces air, which has been carefully filtered through cotton-wool, to be visibly pure; there are no germs afloat in it; hence it is impossible as a generator of life. Again, Pasteur prepared twenty-one flasks, each containing a decoction of yeast, which he boiled in order to destroy whatever germs it might contain. While the space above the liquid was filled with pure steam he sealed the necks of his flasks with a blow-pipe. He opened ten of them in the damp, still caves of the Paris Observatory, and eleven of them in the courtyard of the same establishment. Of the former only one showed signs of life subsequently. In nine out of the ten flasks no organisms of any kind were developed. In all the others organisms speedily appeared. Pasteur ascribed this unexpected result to the subsidence of the germs in the motionless air of the caves. Is this surmise correct? The beam of light enables us to answer this question. I have had a chamber constructed, the lower half of which is of wood, and the upper half of glass. On the 6th February this chamber was closed, and every crevice that could admit dust or cause a disturbance of the air was carefully stopped. The electric beam when sent through the glass showed the air at the outside to be loaded with floating matter. The chamber was examined almost daily, and a gradual diminution of the floating matter was observed. At the end of the week the chamber was optically empty. The floating matters, germs included, had wholly subsided, and the air held nothing in suspension. Here again the ocular demonstration furnished by the luminous beam goes hand in hand with the experimental result of Pasteur.”
Professor Tyndall did not, however, adopt the germ theory on the authority of Pasteur. He not only discovered it for himself, but demonstrated its accuracy by innumerable experiments, in the course of which he made use of 10,000 vessels. To him, too, science owes the use of the electric beam as an explorer of germ particles which could not otherwise be made visible by the best optical aids. The most exquisitely minute particles, which could not be detected by the most powerful glasses, have been revealed in the air by the electric beam.
For some time he carried on a controversy with some doughty champions of the old theory of spontaneous generation; but as the evidences in favour of the germ theory increased, the antagonism to it diminished. One practical evidence, not only of the reality, but of the utility of the germ theory, was Pasteur’s discovery of the nature of the organisms in yeast that produced “beer disease;” and when Pasteur visited England, after that discovery, and explained the cause of beer turning sour, Professor Tyndall afterwards visited some of the most prominent breweries in London to make inquiries on the subject. He was extremely surprised at the paucity of knowledge possessed by the brewers, although they had over and over again incurred disastrous losses in consequence of their lack of knowledge. He said that when the brewers found their beer becoming bad they used to exchange their yeast among themselves, and thus get on with their losses, when five minutes’ examination with the microscope would have prevented this waste and loss; for it would have shown them the minute organisms which spoiled the beer.
In connection with his researches on the germ theory, he produced a useful invention which had a philanthropic rather than a commercial object. To the title of inventor he never made any claim; on the contrary, he repeatedly expressed his view of the difference between a scientific discoverer and a mechanical inventor; contending that while the practical man is not usually the man to make the necessary antecedent discoveries, the cases are rare in which the discoverer in science knows how to turn his labours to practical account.
Nevertheless scientific reflection enabled him to devise a form of respirator which protects firemen from the stifling effects of dense smoke. His attention had repeatedly been directed to the risks that firemen encountered when in conflict with smoke and flame, and he had been told that smoke was a greater enemy to them than flame. He therefore endeavoured to find a means of protecting them from suffocation. First he tried a respirator made of cotton-wool, but that was insufficient; so to the cotton-wool he added glycerine; and though this was an improvement, still it only enabled them to remain in dense smoke for three or four minutes. He next added charcoal and this greatly increased the utility of the respirator, which when complete was composed of a layer of cotton-wool moistened with glycerine, next a thin layer of dry wool, then a layer of charcoal fragments, succeeded by another thin layer of dry cotton-wool and a layer of fragments of caustic lime. These were inclosed in a wire gauze cover. The first experiments with this respirator were made in a small cellar-like chamber with stone flooring and stone walls in the basement of the Royal Institution. A fire of resinous pine-wood was lighted, and was so covered over as to generate dense smoke instead of flames. Professor Tyndall and his assistant, having each put on one of the new respirators, and suitable glasses to protect their eyes, were able to remain for half an hour or longer in that apartment full of smoke so dense and pungent that he believed a single inhalation through the undefended mouth would have been perfectly unendurable. Captain Shaw, the chief officer of the Metropolitan Fire Brigade, on being asked whether such a respirator would be of use to him, replied that it would be most valuable; but he had made himself acquainted with every contrivance of the kind in this and other countries, and had found none of them of any practical use. However, at the request of Professor Tyndall, the Captain and some of his men went to the Royal Institution to test the new invention. The small room was again filled with dense smoke, three men went successively into it, and remained there as long as their Captain desired. On coming out they declared that with the respirators they had not felt the least discomfort, and that they could have remained all day in the smoke. Captain Shaw himself then tested it with the same result, and he afterwards stated that Professor Tyndall, in the kindest possible manner, at once placed his invention at the service of the Fire Brigade.
In 1870 he accompanied the eclipse expedition to Oran, and having been disappointed in the special object of his journey, he determined in returning to investigate the causes of the varying tints presented by sea-water. On board H.M.S. Urgent, between Gibraltar and Spithead, he filled nineteen bottles with sea-water, and afterwards examined them by the electric light. This examination showed that the yellowish water of the coast and harbours contained a large quantity of particles, that in the green water the particles were finer and less abundant, and that the blue water of the deep was comparatively clear of them. The explanation he gave of the colours of the ocean, in a lecture at the Royal Institution, was that when a beam of light entered the sea the heat-rays were absorbed at the surface, the red rays by a very superficial layer of water, the green rays next, and ultimately the blue rays; but when the light encountered particles in the water the green rays would be reflected by them. If there were no particles, the green rays would continue their course till they were wholly quenched, and thus water of more than ordinary depth and purity would appear as black as ink.
In later years he made some practical additions to our knowledge of sound. His advice had repeatedly been asked as to the laws which affected the distribution of sound variously in different buildings—a subject upon which volumes had been written, but which was still imperfectly understood. As an illustration of the unexpected circumstances that affected the transmission of sound, he sometimes related what occurred to himself in the Senate House of Cambridge University when he delivered the Rede lecture in 1865. On going to the Senate House to test its acoustic qualities, he was astonished to find that from the usual place of speaking his words could not be heard at all by a friend whom he had placed at the extreme end of the hall as his auditory. He found that the reverberation from the floor and walls followed the direct sound of his voice in such a way as to destroy the clearness of the words as they were uttered. Dismayed at this effect, he made up his mind that in respect of audibleness his lecture was doomed to be a failure. But the reverse was the case. The lecture was in every respect a great success. An overflowing audience filled the hall, and listened to him with rapt attention. During the hour and a half that he spoke every syllable was heard by the most distant hearer; and he attributed this unexpected result to the presence of the audience, which, he said, quenched the prejudicial effect of the reverberation of his voice produced by the sides and bottom of the room. After that experience, he advocated the making of different experiments with the view of extending the practical knowledge of acoustics.
To that knowledge he himself became a valuable contributor. In 1873 he conducted a series of experiments with a view to determine the properties of the atmosphere as a vehicle of sound. Navigators had often been at a loss to understand how it was that the most powerful fog-signals—such as gongs, whistles, and guns—were sometimes easily heard at a great distance on rainy days, and were inaudible at comparatively short distances on fine days. Even within a few minutes the acoustic properties of the atmosphere sometimes underwent remarkable variations. Professor Tyndall’s experiments led him to the conclusion that the aqueous vapour raised by the sun, though often invisible, produced a cloud which formed as impervious a barrier to the waves of sound as a dense black cloud does to the waves of light. The presence of water in a vaporous form being the real enemy to the transmission of sound through the atmosphere, it was easy to understand its frequent occurrence on days apparently clear and bright. This was previously unknown.
He also furnished an interesting illustration of the corelation of heat and sound.
Notwithstanding the elaborate data upon which he had founded his conclusions as to the interaction of radiant heat on vapours, some Continental physicists questioned their accuracy, and accordingly Professor Tyndall in later years resumed the inquiry and obtained some remarkable results. He had previously shown that heat will pass without any loss through a long glass tube filled with nitrogen or air, and closed up at the ends by lenses of crystal; but if the same tube is filled with carbonic acid or the vapour of ether the heat, instead of being transmitted through it, is almost entirely intercepted. In 1880 Mr. Graham Bell showed him that musical sounds were produced by a beam of light striking upon thin discs of matter; and Professor Tyndall at once discovered the secret of this surprising effect. He said that before making an experiment he pictured in his mind a highly-absorbent vapour exposed to the shocks of an intermittent beam suddenly expanding at the moment of exposure, and as suddenly contracting when the beam was intercepted; and thus pulses of an amplitude probably far greater than those obtainable with solids would be produced, and would be sufficient to give forth musical sounds. He soon proved this surmise to be correct. He filled a glass tube or bulb with absorbent gas or vapour, and between it and the limelight he placed a round piece of cardboard with equi-distant holes in it; then by placing the bulb in such a position that when the light passed through the holes it impinged upon the glass bulb, and by causing the cardboard to revolve, the action of the beam became intermittent, as it only reached the vapour when one of the holes in the revolving cardboard came in front of the bulb. By this contrivance a series of calorific shocks were produced that gave sound vibrations of surprising intensity. When, however, the bulbs were filled with gases or vapours, such as nitrogen or air, that transmitted the heat, no sounds were produced. He tried the sounding power of ten gases and eighty vapours, and found that the sounds produced by chloride of methyl were the loudest; and that, conveyed to the ear by a tube of indiarubber, they seemed as loud as the peal of an organ. He also found that in respect of intensity the order of the sound in gases was the same as the order of their absorption of radiant heat. These marvellous results he described in his Bakerian lecture for 1881, “On the Action of Free Molecules on Radiant Heat and its Conversion thereby into Sound.”
FOOTNOTES:
[3] This glacier theory is all the more deserving of prominence since the publication in 1886 of Lieutenant Greely’s discovery of lakes, rivers, and valleys rich in vegetation and animal life in the interior of Grinnell Land at points the farthest north ever reached by explorers.
CHAPTER IV.
“Undaunted he hies him
O’er ice-covered wild,
Where leaf never budded,
Nor spring ever smiled;
And beneath him an ocean of mist, where his eye
No longer the dwellings of man can espy.”
—Schiller.
As a traveller in search of Nature’s grandest works, Professor Tyndall occupies a foremost place for his adventures in Alpine regions previously regarded as unapproachable, as well as for his descriptions of the views presented and the sentiments inspired by those peaks of everlasting snow. The narrative of his achievements as an Alpine traveller fills a larger volume than this one. Two or three specimens must therefore suffice here. The following is the account he gave in a letter to Faraday in August, 1858, of his ascent of Monte Rosa, which was then considered much more difficult to climb than Mont Blanc:—
“I reached this mountain wild the day before yesterday. Soon after my arrival it commenced snowing, and yesterday morning the mountains were all covered by a deep layer. It heaped itself up against the windows of this room, obscuring half the light. To-day the sun shines, and I hope he will soon banish the snow, for the snow is a great traitor on the glacier, and often covers smooth chasms which it would not be at all comfortable to get into. I am here in a lonely house, the only traveller. If you cast your eye on a map of Switzerland you will find the valley of Saas not far from Visp. High up this valley, and three hours above Saas itself, is the Distil Alp, and on this Alp I now reside. Close beside the house a many-armed mountain torrent rushes, and a little way down a huge glacier, coming down one of the side valleys, throws itself across the torrent, dams it up, and forms the so-called ‘Matmark See.’ Looking out of another window I have before me an immense stone, the unshipped cargo of a glacier, and weighing at least 1,000 tons. It is the largest boulder I have ever seen; it is composed of serpentine, and measures 216,000 cubic feet. Previous to coming here I spent ten days at the Riffel Hotel, above Zermatt, and explored almost the whole of that glacier region. One morning the candle of my guide gleamed into my room at three o’clock, and he announced to me that the weather was good. I rose, and at four o’clock was on my way to the summit of Monte Rosa. My guide had never been there, but he had some general directions from a brother guide, and we hoped to be able to find our way to the top. We first reached the ridge above the Riffel, then dropped down upon the Görner glacier, crossed it, reached the base of the mountain, then up a boss of rock, over which the glacier of former days had flowed and left its mark behind. Then up a slope of ice to the base of a precipice of brown crags: round this we wormed till we found a place where we could assail it and get to the top. Then up the slopes and round the huge bosses of the mountain, avoiding the rifted portions, and going zigzag up the steeper inclinations. For some hours this was mere child’s play to a mountaineer—no more than an agreeable walk on a sunny morning round Kensington Gardens. But at length the mountain contracted her snowy shoulders to what Germans call a kamus—a comb, suggested, I should say, by the toothed edges which some mountain ridges exhibit, but now applied to any mountain edge, whether of rock or snow. Well, the mountain formed such an edge. On that side of the edge which turns toward the Lyskamm there was a very terrible precipice, leading straight down to the torn and fissured névé of the Monte Rosa glaciers. On the other side the slope was less steep, but exceedingly perilous-looking, and intersected here and there by precipices. Our way lay along the ledge, and we faced it with steady caution and deliberation. The wind had so acted upon the snow as to fold it over, forming a kind of cornice, which overhung the first precipice to which I have alluded. Our attack for some time was upon this cornice. The incessant admonition of my guide was to fix my staff securely into the snow at each step, the necessity of which I had already learned. Once, however, while doing this, my staff went right through the cornice, and I could see through the hole that I had made into the terrible gulf below. The morning was clear when we started, and we saw the first sunbeams as they lit the pinnacles of Monte Rosa, and caused the surrounding snow summits to flush up. The mountain remained clear for some hours, but I now looked upwards and saw a dense mass of cloud stuck against the summit. She dashed it gallantly away, like a mountain queen; but her triumph was short. Dusky masses again assailed her, and she could not shake them off. They stretched down towards us, and now the ice valley beneath us commenced to seethe like a boiling cauldron, and to send up vapour masses to meet those descending from the summit. We were soon in the midst of them, and the darkness thickened; sometimes, as if by magic, the clouds partially cleared away, and through the thin pale residue the sunbeams penetrated, lighting up the glacier with a supernatural glare. But these partial illuminations became rarer as we ascended. We finally reached the weathered rocks which form the crest of the mountain, and through these we now clambered up cliffs and down cliffs, walking erect along edges of granite with terrible depths at each side, squeezing ourselves through fissures, and thus jumping, swinging, squeezing, and climbing, we reached the highest peak of Monte Rosa.
“Snow had commenced to fall before we reached the top, and it now thickened darkly. I boiled water, and found the temperature 184·92° Fahr. But the snow was wonderful snow. It was all flower—the most lovely that ever eye gazed upon. There, high up in the atmosphere, this symmetry of form manifested itself and built up these exquisite blossoms of the frost. There was no deviation from the six-leaved type, but any number of variations. I should hardly have exchanged this dark snowfall for the best view the mountain could afford me. Still, our position was an anxious one. We could only see a few yards in advance of us, and we feared the loss of our track. We retreated, and found the comb more awkward to descend than to ascend. However, the fact of my being here to tell all about it proves that we did our work successfully. And now I have a secret to tell regarding Monte Rosa. I had no view during the above ascent, but precisely a week afterwards the weather was glorious beyond description. I had lent my guide to a party of gentlemen, so I strapped half a bottle of tea and a ham sandwich on my back, left my coat and neckcloth behind me, and in my shirt sleeves climbed up Monte Rosa alone.” The latter act has been described as a feat of daring never heard of before.
Between 1856 and 1862 he ascended Mont Blanc three times. One ascent, made in 1859, was for the purpose of carrying into effect a proposal he had made to the Royal Society some months previously to place suitable thermometers at different stations between the top and the foot of the mountain. On that occasion he was accompanied by his friend Dr. Franklin, the notable guide Balmat, Mr. Alfred Wills, and several porters. Professor Tyndall afterwards gave a graphic account of the ascent to the British Association at Leeds, when he spoke in the highest terms of the services rendered by Balmat. Mr. Wills says he made the Leeds Town Hall ring with well-deserved applause as he recounted to the first savants in Europe the dangers Balmat had undergone, and the courage and disinterestedness he displayed. The ascent was made late in September in fearful weather, and in order to cut a hole four feet deep in the solid glacier, Balmat used his hands for shovelling out the ice and snow, till both hands were soon found to be badly frost-bitten and quite black. When the circulation began to return, after half-an-hour’s rubbing and beating, he suffered great agony; and though he was for some time in danger of losing his hands, he said he could have endured even that calamity in the cause of science.
In August, 1861, Professor Tyndall succeeded in reaching the top of the Weisshorn, a mountain 14,800 feet high, which he regarded as the noblest peak in the Alps. People at the base described him and his two guides as appearing like flies upon the summit. “I never,” he said afterwards, “witnessed a scene that affected me like this one. I opened my note-book to make a few observations, but soon relinquished the attempt. There was something incongruous, if not profane, in allowing the scientific faculty to interfere where silent worship seemed the ‘reasonable service.’” In like manner Principal Forbes, who preceded but did not equal Professor Tyndall as an Alpine traveller, said that “the seeds of a poetic temperament usually germinate amidst mountain scenery, and we envy not the man, young or old, to whom the dead silence of sequestered nature does not bring an irresistible sense of awe—an experience which a picturesque writer has thus expressed: It seems impious to laugh so near Heaven,” Hence probably the words of Byron:—
“There stirs the feeling infinite, so felt
In solitude, when we are least alone;
A truth, which through our being then doth melt,
And purifies from self: it is a tone,
The soul and source of music, which makes known
Eternal harmony, and sheds a charm,
Like to the fabled Cytherea’s zone,
Binding all things with beauty;—’twould disarm
The spectre Death, had he substantial power to harm.”
Professor Tyndall translated such sentiments into actions. At the time when he began to ascend the highest of those Alpine peaks, accidents of the most painful description were frequently reported as occurring to travellers, owing to the absence of that more intimate knowledge of the routes and methods of travelling which has since been acquired by experience or revealed by science—knowledge which he himself rendered generous and valuable aid in acquiring and diffusing. For instance, while he was at Breuil on August 18th, 1860, intelligence reached him that three Englishmen and a guide had perished on the Col-du-Géant. The more he heard of the sad occurrence, he said, the stronger became his desire to visit the scene of it. He accordingly went to Cormayeur on the 22nd, and called on the resident French pastor, M. Curie, who had visited the place and made a sketch of it. Accepting this gentleman’s offer to accompany him, Professor Tyndall reached the Pavilion early on the morning of Thursday, the 24th. “Wishing,” says the Professor, “to make myself acquainted with every inch of the ground over which, from the commencement of their glissade, the unfortunate men had passed, I walked straight up from the Pavilion to the base of the rocky couloir along which they had been precipitated. This couloir was described as being so dangerous that a chamois hunter had declined ascending it some days before; but I secured at Cormayeur the service of an intrepid man who had once made the ascent, and whom it was now my intention to follow. We commenced our climb at the very bottom of the rocks, while the pastor made a détour and joined us on the spot where the body of the guide had been found. From this point upward, M. Curie shared the dangers of the ascent—strongly, I confess, against my will—until we reached the place where the rocks ended and the fatal snow slope commenced. Here we parted company, he deeming it more prudent to resort to a stony arête to the right than to trust himself upon the snow. I was urged by M. Curie to content myself with an inspection of the place, but no inspection, however close, could have given the information I desired. I asked my guide whether he feared the slope, and his reply being negative, we entered upon the snow, and ascended it along the course of the fatal glissade, the traces of which had not been entirely obliterated. Among the rocks below we had frequent and often melancholy occasion to assure ourselves that we were on the proper track.... From the beginning to the end of this fatal track, I made myself acquainted with its true character, and as I stood upon the summit of the incline and scanned the ground over which I had passed a feeling of augmented sadness took possession of me. There was no sufficient reason for this terrible catastrophe. With ordinary precaution the glissade might in the first instance have been avoided, and with average capacity to cope with such an accident the motion might, I am persuaded, have been arrested after it commenced.”
He concluded a long letter to the Times, from which the foregoing extract is taken, by saying that the guides of Chamouni ought to regard this terrible disaster as a stain upon their order which it would require years of services faithfully and wisely rendered to wipe away. It is much easier to censure than to set a good example, and from that point of view Professor Tyndall was blamed at the time for being so severe in his strictures. Ere long, however, an opportunity occurred which put his own resources to the severest test. While staying at Pontresina in 1864, he, along with Mr. Hutchinson and Mr. Lee-Warner, of Rugby, ascended the Piz Morteratch, a very noble mountain, which was thought safe and easy to ascend. The top was reached without any exceptional difficulty; but in descending they came to a broad couloir filled with snow, which, having been melted and refrozen, appeared like a sloping wall of ice. The party were tied together, with one guide named Jenni in front, and another named Walter in the rear. Jenni cut steps in the ice, and then reached snow, which he expected would give them a footing. As he led the party he said, “Keep carefully in the steps, gentlemen; a false step here might detach an avalanche.” The word was scarcely uttered, says the Professor, whose account has been corroborated by his companions, “when I heard the sound of a fall behind me, then a rush, and in a moment my two friends and their guide, all apparently entangled together, whirled past me. I suddenly planted myself to resist their shock, but in an instant I was in their wake, for their impetus was irresistible. A moment afterwards Jenni was whirled away, and thus, in the twinkling of an eye, all five of us found ourselves riding downwards with uncontrollable speed on the back of an avalanche which a single slip had originated.
“Previous to stepping on the slope, I had, according to habit, made clear to my mind what was to be done in case of mishap; and accordingly, when overthrown, I turned promptly on my face, and drove my bâton through the moving snow, and into the ice underneath. No time, however, was allowed for the break’s action; for I had held it firmly thus for a few seconds only when I came into collision with some obstacle and was rudely tossed through the air, Jenni at the same time being shot down upon me. Both of us here lost our bâtons. We had been carried over a crevasse, had hit its lower edge, and, instead of dropping into it, were pitched by our great velocity far beyond it. I was quite bewildered for a moment, but immediately righted myself, and could see the men in front of me half buried in the snow, and jolted from side to side by the ruts among which we were passing. Suddenly I saw them tumbled over by a lurch of the avalanche, and immediately afterwards found myself imitating their motion. This was caused by a second crevasse. Jenni knew of its existence and plunged, he told me, right into it—a brave act, but for the time unavailing. By jumping into the chasm he thought a strain might be put upon the rope sufficient to check the motion. But though over thirteen stone in weight, he was violently jerked out of the fissure, and almost squeezed to death by the pressure of the rope.
“A long slope was before us which led directly downwards to a brow where the glacier fell precipitously. At the base of the declivity ice was cut by a series of profound chasms, towards which we were rapidly borne. The three foremost men rode upon the forehead of the avalanche, and were at times almost wholly immersed in the snow; but the moving layer was thinner behind, and Jenni rose incessantly and with desperate energy drove his feet into the firmer substance beneath. His voice, shouting ‘Halt! Herr Jesus, halt!’ was the only one heard during the descent. A kind of condensed memory, such as that described by people who have narrowly escaped drowning, took possession of me, and my power of reasoning remained intact. I thought of Bennen on the Haut de Cry, and muttered, ‘It is now my turn.’ Then I coolly scanned the men in front of me, and reflected that, if their vis viva was the only thing to be neutralised, Jenni and myself could stop them; but to arrest both them and the mass of snow in which they were caught was hopeless. I experienced no intolerable dread. In fact the start was too sudden and the excitement of the rush too great to permit of the development of terror.
“Looking in advance, I noticed that the slope for a short distance became less steep and then fell as before. ‘Now or never we must be brought to rest.’ The speed visibly slackened, and I thought we were saved. But the momentum had been too great; the avalanche crossed the brow and in part regained its motion. Here Hutchinson threw his arm round his friend, all hope being extinguished, while I grasped my belt and struggled to free myself. Finding this difficult, from the tossing, I sullenly resumed the strain upon the rope. Destiny had so related the downward impetus to Jenni’s pull as to give the latter a slight advantage, and the whole question was whether the opposing force would have sufficient time to act. This was also arranged in our favour, for we came to rest so near the brow that two or three seconds of our average motion of descent must have carried us over. Had this occurred, we should have fallen into the chasm, and been covered up by the tail of the avalanche. Hutchinson emerged from the snow with his forehead bleeding, but the wound was superficial; Jenni had a bit of flesh removed from his hand by collision against a stone; the pressure of the rope had left black welts on my arms; and we all experienced a tingling sensation over the hands, like that produced by incipient frost-bite, which continued for several days. This was all.”
Another incident which illustrates the nature and variety of his experience as a traveller he has himself described as prompted more by the instincts of the mountaineer than by the curiosity of the man of science. In 1868 he visited Vesuvius; and if he did not collect information of much scientific value, he saw a good deal that was very interesting. He said he was most struck with the condition of the country all round Naples; it was so seething, and smoking, and hot, showing the presence of vast subterranean fires. It was the same at Vesuvius, where in one place at the entrance to a gallery in the side of the mountain, he found a little boy quite naked, who volunteered to enter the gallery and cook an egg which he held in his hand. Both the Professor and his companion (Sir John Lubbock) determined to explore the gallery. On doing so they found at the end of it a hot salt spring, where they cooked the egg. The guide told them of a hotter gallery adjoining, which they also explored; and a hotter one still being pointed out, they likewise tried it and found it very hot indeed. They also visited the grotto Del Cano, where the floor was covered with carbonic acid gas, a broad stream of which flowed out of the mouth of the cavern. There he performed what he called some of the commoner Royal Institution experiments for the benefit of the natives. He collected some of the heavy gas in his hat, carried it to a distance, and then put out lighted matches by pouring the heavy gas over them. A little dog being kept near the cave for the purpose of showing visitors how easily the gas could half choke it, he protested against the cruelty of that experiment. At Pompeii, he came to the conclusion that the ashes which burned it could not have been of very high temperature when they fell, having been much chilled by their previous passage through the air. Among the evidences of this was the fact that a fountain of pure lead, which was uncovered during the excavations, was uninjured. The analysis of a piece which he took away with him showed that the temperature of the ashes in which it was engulfed, was lower than the melting point of lead. In ascending Vesuvius they crossed a ridge which formed the ancient crater of the mountain; others had been thrown up since, the latest being 300 feet higher than the ancient one. Vesuvius, he said, was nineteen feet higher in 1868 than it had ever been before in human history. In the midst of the smoking centres of eruption, they listened to the noises in the mountain beneath, and saw three discharges of red-hot stones from the crater. The wind was so strong that one gust blew down Sir John Lubbock on his face. On another occasion when they ascended the mountain, they were favoured with a strong wind, and going further than the guide would lead them, they went to the edge of the principal crater, and looked down into the great central hole of the volcano itself, where they saw little but smoke and a lurid glare. Sometimes they were enveloped in smoke and sulphurous acid gas, but they avoided any risk from it by keeping well to windward. As to the dispute among geologists on the question whether the cones on the top of Vesuvius were made by eruption or upheaval, he came to the same conclusion as Lyell, that they were craters of eruption. It was afterwards estimated that during the eruption which was in progress at the time of Professor Tyndall’s visit, Mount Vesuvius emitted about 20,000,000 cubic feet of lava.
His travels and explorations in another part of the world where Nature displays her operations on a grand scale, and where personal achievement is the only recognised title to fame, were still more memorable. When in June, 1851, Professor Tyndall came back from Germany to England, he met on his way to the meeting of the British Association at Ipswich “a man who has since made his mark upon the intellect of his time,” and to whom he was ever afterwards attached by the strong law of mental affinity. This was Professor Huxley, and both the young scientists being then on the look out for work, they determined to apply for the vacant chairs of natural history and physics in the University of Toronto, but their applications were declined. Faraday, who was Tyndall’s philosopher and friend in the matter, wrote a letter urging him to apply for the Toronto appointment; but happily for both of them and for the glory of British science, Toronto would not have them, and England could not spare them. Twenty years after that Professor Tyndall visited the United States, whence his reputation as a scientific lecturer had preceded him. No people are so quick in their observations of men and manners as the Americans, and it may therefore be opportune here to give an American’s impressions of the man to whom that people gave an enthusiastic reception in 1872. Mr. George Ripley gave the following description of him:—
“Professor Tyndall has all the ardour of a reformer, without any tendency to vague and rash speculations. Recognising whatever is valuable in the researches of a former age, he extends a gracious hospitality to new suggestions. With a noble pride in his favourite branches of inquiry, he is not restricted to an exclusive range of research, but extends his intellectual vision over a wide field of observation. The English, as a rule, are inclined to be suspicious of a man who ventures beyond a special walk in the pursuit of knowledge. They have but little sympathy with the catholic taste which embraces a variety of objects, and is equally at home in the researches of science, the speculations of philosophy, the delights of poetry, and the graces of elegant literature. But a single exception to this trait is presented by Professor Tyndall. His mind is singularly comprehensive in its tendencies, and betrays a versatility of aptitude and a reach of cultivation, which are rarely found in unison with conspicuous eminence in purely scientific pursuits. In his own special domain his reputation is fixed. His expositions of the theory of heat and light and sound, and of some of the more interesting Alpine phenomena, are acknowledged to be masterpieces of popular statement, to which few parallels can be found in the records of modern science. But, in addition to this, he possesses a rare power of eloquence and manifold attainments in different departments of learning. I do not know that he has ever written poetry, but he is certainly a poet in the fire of his imagination and in his love for all the forms of natural beauty. Nor has he disdained to make himself familiar with the leading metaphysical theories of the past age, in spite of the disrepute and comparative obscurity into which science has been thrown by the brilliant achievements of physical research. I noticed with pleasure in his conversation his allusions to Fichte, Goethe, R. W. Emerson, Henry Heine, and other superior lights of the literary world, showing an appreciation of their writings which could only have been the fruit of familiar personal studies. Besides the impression produced on a stranger by his genius and learning, I may be permitted to say that I have met with few men of more attractive manners. His mental activity gives an air of intensity to his expression, though without a trace of vehemence, or an eager passion for utterance. In his movements he is singularly alert, gliding through the streets with the rapidity and noiselessness of an arrow, paying little attention to external objects; and, if you are his companion, requiring on your part a nimble step and a watchful eye not to lose sight of him. Though overflowing with thought, which streams from his brain as from a capacious reservoir while his words ‘trip around as airy servitors,’ he is one of the best of listeners, never assuming an undue share of the talk, and lending an attentive and patient ear to the common currency of conversation, without demanding of men the language of the gods. The singular kindness of his bearing, I am sure, must proceed from a kind and generous heart. With no pretence of sympathy, and no uncalled for demonstrations of interest, his name will certainly be set down by the recording angel as one who loves his fellow men.”
Such was the man who had now come amongst the Americans to enjoy their hospitality and to enlighten them on the subject of light. He delivered a course of lectures at Boston, New York, Philadelphia, Baltimore, and Washington. At Boston, he said he would long gratefully remember his reception on the occasion of his first lecture there, and that if he was treated in the same manner elsewhere he would return to the old country full of gratitude. Other places tried to outdo Boston in the cordiality of their reception. The halls in which he lectured were crowded by audiences described as distinguished for their appreciation of learning and their enthusiasm in the presence of “the great teacher.” His lectures were reported verbatim with illustrations in the daily newspapers; and the New York Tribune published a cheap reprint of them of which over 300,000 were sold.
While in America he did not miss an opportunity not only of inspecting but of exploring its grandest cataract. With him the roar of the waterfall was early a subject of scientific investigation. At a meeting of the British Association in 1851 he showed by some simple experiments that water falling for a certain distance into another vessel of water would produce neither air-bubbles nor sound; but that, as soon as the distance is so increased that the end of the column becomes broken into drops, both air-bubbles and sounds, varying from the hum of the ripple to the roar of the cataract and of the breaker, were produced. About the same time he published a paper in the Philosophical Magazine for the purpose of showing that in waterfalls sound was produced by the bursting of the bubbles, and he therein stated that “were Niagara continuous and without lateral vibration, it would be as silent as a cataract of ice. It is possible, I believe, to get behind the descending water at one place; and if the attention of travellers were directed to the subject, the mass might perhaps be seen through. For in all probability it also has its ‘contracted sections;’ after passing which it is broken into detached masses, which, plunging successively upon the air-bladders formed by their precursors, suddenly liberate their contents, and thus create the thunder of the waterfall.”
On the 1st of November, 1872, he visited Niagara, and not only got behind the descending water, but “saw through” it, and afterwards graphically described it. He states that “the season” being then over, the scene was one of weird loneliness and beauty. On reaching the village he at once proceeded to the northern end of the American Fall. After dinner he, accompanied by a friend, crossed to Goat Island and went to the southern end of the American Fall. “The river is here studded with small islands. Crossing a wooden bridge to Luna Island, and clasping a tree which grows near its edge, I looked long at the cataract which here shoots down the precipice like an avalanche of foam. It grew in powder and beauty as I gazed upon it. The channel, spanned by the wooden bridge, was deep, and the river there doubled over the edge of the precipice, like the swell of a muscle, unbroken. The ledge here overhangs, the water being poured out far beyond the base of the precipice. A space, called the Cave of the Winds, is thus inclosed between the wall of rock and the cataract.
“At the southern extremity of the Horseshoe is a promontory, formed by the doubling back of the gorge, excavated by the cataract, and into which it plunges. On the promontory stands a stone building called the Terrapin Tower, the door of which had been nailed up because of the decay of the staircase within it. Through the kindness of Mr. Townsend, the superintendent of Goat Island, the door was opened to me. From this tower, at all hours of the day, and at some hours of the night, I watched and listened to the Horseshoe Fall. The river here is evidently much deeper than the American branch; and instead of bursting into foam where it quits the ledge, it bends solidly over and falls in a continuous layer of the most vivid green. The tint is not uniform but varied; long stripes of deeper hue alternating with bands of brighter colour. Close to the ledge over which the water falls, foam is generated, the light falling upon which and flashing back from it is shifted in its passage to and fro, and changed from white to emerald green. Heaps of superficial foam are also formed at intervals along the ledge, and immediately drawn down in long white striæ. Lower down, the surface, shaken by the reaction from below, incessantly rustles into whiteness. The descent finally resolves itself into a rhythm, the water reaching the bottom of the fall in periodic gushes. Nor is the spray uniformly diffused through the air, but is wafted through it in successive veils of gauze-like texture. From all this it is evident that beauty is not absent from the Horseshoe Fall, but majesty is its chief attribute. The plunge of the water is not wild, but deliberate, vast, and fascinating.”
On the first evening of his visit the guide to the Cave of the Winds, a strong-looking and pleasant man, told him that he once succeeded in getting almost under the green water of the Horseshoe Fall. Professor Tyndall asked whether the guide could lead him to that spot to-morrow. Such a cool question coming from a slender and refined-looking man seemed to non-plus the guide; but on being assured that where he would lead the Professor would endeavour to follow, the guide, with a smile, said “Very well, I shall be ready for you to-morrow.” They met according to agreement on the morrow. First the Professor had to change his clothes drawing on two pairs of woollen pantaloons, three woollen jackets, two pairs of socks, and a pair of felt shoes, which supply of woollens the guide said would preserve him from cold. Over all was put a suit of oil-cloth, and the Professor was advised to carry a pitchfork as his staff. It was decided to take the Horseshoe first as being the most difficult of access. Descending the stairs they commenced to cross the huge boulders which cover the base of the first portion of the cataract, and among which the water pours in torrents. They got along without difficulty till they came to a formidable current, and the guide on reaching the quietest part of it, told the Professor that this was their greatest difficulty; “if we can cross here,” he said, “we shall get far towards the Horseshoe.” The guide entered the torrent first, and was soon up to the waist in water. He had to wade his way among unseen boulders which increased the violence of the current. On reaching the shallower water on the other side, he stretched his arm across to the Professor and asked him to follow. “I looked,” says the undaunted traveller, “down the torrent as it rushed to the river below, which was seething with the tumult of the cataract. I entered the water. As it rose around me, I sought to split the torrent by presenting a side to it; but the insecurity of the footing enabled it to grasp the loins, twist me fairly round, and bring its impetus to bear upon the back. Further struggle was impossible, and feeling my balance hopelessly gone, I turned, flung myself towards the bank I had just quitted, and was instantly swept into the shallower water.”
The oil-cloth covering, which was too large for him, was now filled with water, and notwithstanding this incumbrance, the guide urged him to try again. After some hesitation he determined to do so. Again he entered the water, again the torrent rose, again he wavered; but instructed by the experience of his first misadventure, he so adjusted himself against the stream that he was able to remain upright. At length they were able to clasp hands, and on thus reaching the other side he was told that no traveller had ever been there before. Soon afterwards he was again taken off his feet through trusting to a piece of treacherous drift, but a protruding rock enabled him to regain his balance. As they clambered over the boulders the weight of the thick spray now and then caused them to stagger. Among such volumes of spray nothing could be seen. “We were,” he says, “in the midst of bewildering tumult, lashed by the water which sounded at times like the cracking of innumerable whips. Underneath this was the deep resonant roar of the cataract. I tried to shield my eyes with my hands and look upwards; but the defence was useless. My guide continued to move on, but at a certain place he halted, and desired me to take shelter in his lee and observe the cataract. On looking upwards over the guide’s shoulder I could see the water bending over the ledge, while the Terrapin Tower loomed fitfully through the intermittent spray gusts. We were right under the tower. A little farther on the cataract, after its first plunge, hit a protuberance some way down, and flew from it in a prodigious burst of spray; through this we staggered. We rounded the promontory on which the Terrapin Tower stands, and pushed, amidst the wildest commotion, along the arm of the Horseshoe until the boulders failed us and the cataract fell into the profound gorge of the Niagara River. Here my guide sheltered me again, and desired me to look up. I did so, and could see as before the green gleam of the mighty curve sweeping over the upper ledge, and the fitful plunge of the water as the spray between us and it alternately gathered and disappeared. My companion knew no more of me than that I enjoyed the wildness; but as I bent in the shelter of his large frame, he said: ‘I should like to see you attempting to describe all this.’ He rightly thought it indescribable.” Their egress was nearly as adventurous as their entrance. They had another struggle with the torrent which proved such a formidable barrier in entering, but they succeeded in crossing it without serious mishap.
He next endeavoured to see the fall from the river below it; but on reaching the base of the Horseshoe he found the water so violent, and the rock and boulders so formidable, that after a fierce struggle the attempt to go further had to be relinquished. He therefore returned along the base of the American Fall. “Seen from below,” says the Professor, “the American Fall is certainly exquisitely beautiful, but it is a mere fringe of adornment to its nobler neighbour, the Horseshoe. At times we took to the river, from the centre of which the Horseshoe Fall appeared especially magnificent. A streak of cloud across the neck of Mont Blanc can double its apparent height, so here the green summit of the cataract, shining above the smoke of spray, appeared lifted to an extraordinary elevation.”[4]
In his American lectures he never appeared to miss an opportunity of telling his audience that the pursuit of scientific truth should be conducted regardless of monetary considerations, and that the men who had made the great discoveries in science that had so enriched the world were not actuated by the love of money. At New York he said the presence there for six inclement nights of an audience, embodying to a great extent the mental force and refinement of the city, showed their sympathy with scientific pursuits. “That scientific discovery may put not only dollars into the pockets of individuals but millions into the exchequers of nations the history of science amply proves, but the hope of its doing so is not the motive power of the investigator. It never could be the motive power.... You have asked me to give these lectures, and I cannot turn them to better account than by asking you to remember that the lecturer is usually the distributor of intellectual wealth amassed by better men. It is not as lecturers but as discoverers that you ought to employ your highest men. Keep your sympathetic eye upon the originator of knowledge. Give him the freedom necessary for his researches; above all things avoiding that question which ignorance so often addresses to genius—What is the use of your work? Let him make truth his object, however impracticable for the time being that truth may appear. If you cast your bread thus upon the waters, then be assured it will return to you though it may be after many days.”
In 1873 his advice appeared to be like seed sown in good ground, for immediately after his visit several munificent gifts were made by private individuals for the promotion of science. His example was also as worthy as his teaching. The profits of his lectures, amounting to nearly 3,000l., he gave as a contribution towards the establishment of a fund for the advancement of theoretic science and the promotion of original research, especially in the department of physics. In the first instance the interest of the fund was to be applied to assisting and supporting two American students with a decided talent for physics; so that they might thus be able to spend at a German university at least four years, of which three should be devoted to the acquisition of knowledge and the fourth to original investigation. Some difficulty being experienced by the trustees in selecting suitable persons, they represented to Professor Tyndall, after some years of experience, that the object aimed at by him would probably be better accomplished by placing the administration of the fund in the hands of some one or more educational institutions, where numbers of young men were always on trial, and where suitable subjects for his benefaction would probably be more easily found. In 1885 Professor Tyndall, acting on this advice, divided the money, which had increased from 13,000$ to 32,000$, into three equal parts, and gave one part to Columbia College, one to Harvard University, and one to the University of Pennsylvania.
On February 4th, 1873, he was entertained at a farewell banquet at New York “in the great hall of the finest restaurant in the world.” On that occasion he stated with regard to the work done and the reception of that work during his visit to America, that nothing could be added to his cup of satisfaction; his only drawback related to the work undone; for he carried home with him the consciousness of having been unable to respond to the invitations of the great cities of the west; but the character of his lectures, the weight of instrumental appliances which they involved, and the fact that every lecture required two days’ possession of the hall—a day of preparation and a day of delivery—entailed heavy loss of time and even severe labour. He then returned to England, where he found many friends ready to welcome him.
Next year (1874) he was President of the British Association, and the address which he delivered at the annual meeting, held that year in Belfast, caused some sensation among “the orthodox.” For this he was not unprepared. He admitted that he had touched on debateable questions, and gone over dangerous ground—and this partly with the view of telling the world that as regards religious theories, schemes, and systems which embrace notions of cosmogony, science claims unrestricted right of search. The address was condemned by the unscientific as veiled materialism, and a flood of sermons and pamphlets were published to expose its “heresies.” One writer went so far as to publish “an inquiry of the Home Secretary as to whether Professor Tyndall had not subjected himself to the penalty of persons expressing blasphemous opinions.”
It seemed to be generally forgotten that Professor Tyndall had stated before the British Association in 1868 that the utmost the materialist “can affirm is the association of two classes of phenomena, of whose real bond of union he is in absolute ignorance. The problem of the connection of body and soul is as insoluble in its modern form as it was in the pre-scientific ages. If you ask him whence is this ‘matter,’ who or what divided it into molecules, he has no answer. Science also is mute in reply to these questions. But if the materialist is confounded and science rendered dumb, who else is entitled to answer? To whom has the secret been revealed? Let us lower our heads and acknowledge our ignorance one and all.” In 1874 he desired to set forth equally “the inexorable advance of man’s understanding in the path of knowledge, and the unquenchable claims of his emotional nature, which the understanding can never satisfy. And if, still unsatisfied, the human mind, with the yearning of a pilgrim for his distant home, will turn to the mystery from which it has emerged, seeking so to fashion it as to give unity to thought and faith—so long as this is done, not only without intolerance or bigotry of any kind, but with the enlightened recognition that ultimate fixity of conception is here unattainable, and that each succeeding age must be held free to fashion the mystery in accordance with its own needs—then, in opposition to all the restrictions of Materialism, I would affirm this to be a field for the noblest exercise of what, in contrast with the knowing faculties, may be called the creative faculties of man.”
Next year, in introducing Sir John Hawkshaw as President of the British Association, Professor Tyndall said his successor would steer the Association through calm water, which would be refreshing after the tempestuous weather which “rasher navigators had thought it their duty to encounter rather than to avoid.” Carlyle says we pardon genial weather for its changes, but the steadiest climate of all is that of Greenland.
FOOTNOTES:
[4] For the descriptions of the Falls of Niagara and of the adventure on the Piz Morteratch we are indebted to the kindness of Professor Tyndall, who readily granted permission to quote them from his copyright works.
CHAPTER V.
“There is something in the contemplation of general laws which powerfully persuades us to merge individual feeling, and to commit ourselves unreservedly to their disposal; while the observation of the calm, energetic regularity of nature, the immense scale of her operations, and the certainty with which her ends are attained, tends irresistibly to tranquillise and reassure the mind, and render it less accessible to repining, selfish, and turbulent emotions.”—J. F. W. Herschel.
The Royal Institution, the scene of Professor Tyndall’s labours, is situated in Albemarle Street, London, and was founded in 1800 by Count Rumford. George III., appreciating the importance of “forming a public institution for diffusing knowledge and facilitating the general introduction of useful mechanical inventions and improvements, and for teaching by courses of philosophical lectures and experiments the application of science to the common purposes of life,” granted it a charter of incorporation in the fortieth year of his reign; and in 1810 the objects of the Institution were extended to the prosecution of chemical science and the discovery of new facts in physical science, as well as the diffusion of useful knowledge. Curiously enough, while the Royal Institution of Great Britain was founded by an American, the great Smithsonian Institute in Washington was founded by an Englishman. As in most institutions founded by private enterprise, the first arrangements made in the Royal Institution were on a humble scale. The building selected for a chemical laboratory was originally a blacksmith’s shop with a forge and bellows; and the physical laboratory remained in its original state for nearly seventy years, during which period it was the scene of the great discoveries of Davy, Faraday, and Tyndall, including the laws of electro-chemical decomposition, the decomposition of the fixed alkalies, the investigation of the nature of chlorine, the philosophy of flame, the condensability of many gases, the science of magneto-electricity, the twofold magnetism of matter, comprehending all known substances, the magnetism of gases, the relation of magnetism and light, the physical effects of pressure on diamagnetic action, the absorption and radiation of heat by gases and vapours, the transparency of our atmosphere, and the opacity of its aqueous vapour to radiant heat. A place hallowed by so many scientific achievements Professor Tyndall desired to preserve, notwithstanding that, owing to the progress made in other scientific institutions, its reputation had changed from that of the best to that of the worst in London; but when he saw that a transformation of the scene was inevitable he did what he could to promote it. Accordingly new laboratories were built in 1872. In reference to this event, Mr. Spottiswoode said in 1873, when he was treasurer to the Institution, that “the one act of wisdom, among the many aberrations of an eccentric member of Parliament, saved Faraday to us, and thereby, as seems probable, our Institution to the country. The liberality of a Hebrew toy-dealer[5] in the east of London, has made the rebuilding of our laboratories possible. It is said that Mr. Fuller, the feebleness of whose constitution denied him at all times and places the rest necessary for health, could always find repose and even quiet slumber amid the murmuring lectures of the Royal Institution; and that in gratitude for the peaceful hours thus snatched from an otherwise restless life, he bequeathed to us his magnificent legacy of £10,000.”
On his return from America in 1873, Professor Tyndall presented to the Royal Institution the new philosophical apparatus that he had used in his lectures in the United States, and it was thereupon resolved to present the warmest congratulations of the members of the Royal Institution “to their Professor of Natural Philosophy upon his safe arrival in England from the United States, in which, upon the invitation of the most eminent scientific men of America, he has been recently delivering a series of lectures unexampled for the interest they have created in that country, and the large and distinguished audiences who have been attracted to them. The members rejoice and welcome him on his return to what they are proud to be able to designate as his own scientific home, with satisfaction and delight, and wish him all continued health and prosperity. They also thank him for his liberal gift to the Institution of the splendid and extensive apparatus employed by him in his lectures in America, and congratulate him on the generous spirit and the love of science which has led him to appropriate the profits of his lectures in the United States to the establishment of a fund to assist the scientific studies of young Americans.”
Another evidence of the respect entertained for him was given on the occasion of his marriage, in 1876, to Lady Louisa Charlotte, eldest daughter of Lord and Lady Claude Hamilton. The ceremony was performed by Dean Stanley in Henry the Seventh’s Chapel, Westminster Abbey; and in commemoration of the event a silver salver with 300 guineas was presented to Professor Tyndall by the members of the Royal Institution, the subscriptions being limited to one guinea each.
Professor A. de la Rue stated in 1843, before Professor Tyndall had begun his scientific studies, that the study of electricity was always a favourite and popular study in England, and as evidence of that observation he added that Professor Faraday had delivered in London lectures on electricity at the Royal Institution, to which resorted in crowds not only men of the world and elegant ladies, who came in great numbers to admire the graces and enjoy the charm which the amiable professor so well knew how to diffuse over his teaching, but also savants who always found something new to acquire from the interesting views of the learned philosopher. These words might with equal propriety be applied to the lectures of Professor Tyndall. During his reign the Royal Institution made marked progress in popularity and usefulness. According to his own statement, the main object of its existence is that of a school of research and discovery; and during the whole time he has been there no manager or member of the Institution ever interfered with his researches, though a bye-law gave them power to do so. The salient features of his researches have already been described; but only those who have had the privilege of hearing the Professor’s own descriptions, and seen his simple and beautiful experiments illustrating the subtle laws of matter, can adequately appreciate the charm with which he invests scientific subjects. It is not an unusual occurrence for the theatre to be full of people nearly an hour before the lecture begins, and whether addressing an audience of young or old people, he rivets attention by his easy, lucid, and fascinating exposition and illustrations of the science of electricity, heat, light, and sound.
As a specimen of the descriptive power with which he can impart interest to a subject generally regarded as unattractive, take the following exposition of the development of electricity:—“Volta found that by placing different metals in contact with each other, and separating every two pairs of metals by what he called a ‘moist conductor,’ he obtained the development of electricity. He imagined that the source of power was simply the contact of the two metals that he employed; he regarded the moist conductor as a neutral body; and his theory was called, in consequence of this view, the ‘contact theory.’ He was perfectly correct in affirming that the contact of different metals produces electricity; one of the metals in contact being positive, and the other being negative. The voltaic current was capable of producing light and heat; but light and heat require the expenditure of power to produce them; and it was shown by Roget that if Volta’s conception were correct, it would be tantamount to the production of a perpetual motion; if the simple contact of metals produced an unfailing source of electricity, it would be the creation of power out of nothing. Here Volta failed. Afterward he devised an instrument which showed the conversion of mechanical power into electricity, and thus into heat and light. That instrument he called the electrophorus, and it furnishes perhaps the simplest means of showing the conversion of mechanical power into electricity, and thence into heat and light. Volta himself was not aware of the doctrines which we now apply to his discoveries. I will go through the form of Volta’s experiment. I have here a piece of vulcanised indiarubber, and I would first remark that when I place a sheet of tin with an insulating handle upon the table and lift it, I simply overcome the gravity of the tin; but if, after having whisked a sheet of vulcanised indiarubber with a fox’s brush, I place the plate upon it, I find that on lifting it something more than the weight of the plate is to be overcome. That plate now is in a different condition from its former one. It is now electrified, and if I bring my knuckle near it I receive an electric spark. What I want to make clear is this: that there is, first of all, the expenditure of an extra amount of mechanical force in order to lift the sheet of tin; that, by the lifting of the tin, you liberate electricity upon its surface; and that then, if you bring your knuckle near it, you receive an electric spark. There is, therefore, first of all, an expenditure of mechanical power in lifting the sheet of tin; then an intermediate stage when the tin is electrified; and finally, the passage through that electric stage into heat. So that you have mechanical power, electricity, and heat; mechanical power and heat being the two extremes of the circuit.
“When you have electricity developed, the connection of heat and light is necessarily accompanied by resistance to the passage of the electricity. The action of lightning conductors, for example, is entirely dependent upon that fact. The chimneys that the conductors protect offer resistance to the passage of the discharge, and therefore would be destroyed by that discharge; but the conductor offering small resistance, the current passes through it without any disruptive action.
“I will explain the principles of an ordinary Grove’s battery, in order to give a better idea of what internal and external resistances there are in the current. In a Grove’s battery there are two metals, zinc and platinum. They are in contact with each other. There are also two liquids, nitric acid and dilute sulphuric acid. If I connect by a wire one end or pole of the battery with the other, I, being close at hand, can see a small spark. There is now flowing through that connecting wire what we call an electric current, which passes from one end of the battery through the wire to the other end. When there is very little resistance offered to the passage of the current, there is no sensible heat developed; but if I sever the wire in the middle and unite the ends by a thin platinum wire, the thin platinum wire introduced into the circuit is first raised to incandescence and then fused. It is because of the resistance that it offers that we see the incandescence of the wire.
“The source of power in this battery is the combustion, for it is to all intents and purposes combustion of the metal zinc. When we connect the two poles of that battery by a thick wire we have no sensible external heat produced. The heat due to the combustion of the zinc is liberated wholly in the cells of the battery itself. That quantity of heat, as is very well known, is the amount developed by the solution or oxidation of zinc in dilute sulphuric acid. Supposing that we allowed the current to pass through the thick wire until a certain definite weight of zinc was dissolved in the battery, that would produce in the cells of the battery a perfectly definite amount of heat. Let us compare that amount of heat with the amount produced in the battery when we introduce the thin platinum wire. In the one case we have no external heat, and in the other we have. The great law which regulates these transactions is this: that the sum of the internal and the external heats is a constant quantity; so that when the platinum wire was ignited we had less heat developed in the battery than before. The zinc in the battery is burned as fuel upon a hearth; the heat, however, being developed either upon the hearth itself or at any distance from it.
“As a primary source of electricity here is the combustion of a metal, the voltaic battery is not an economical source of power for producing electric light. Had it been so we should have employed the electric light long before the present time. Davy, seventy years ago, made most important experiments upon the light and heat of the voltaic circuit, but the reason why it was not applied previously is simply that zinc is an exceedingly expensive fuel. That stopped the economical application of the electric light to the purposes of public lighting.
“If we burnt the zinc in the open air instead of in the battery there would be a considerable amount of heat and light produced. To burn it in the acid fluid of the battery, afterwards converting it into heat and light, is only another mode of burning it: both are due to the same combustion.
“In the year 1820 Arago discovered that when he carried an electric current parallel to a magnetic needle, he deflected the needle to the right or to the left, as the case may be. Soon afterwards one of the greatest geniuses that ever lived, Ampère, within eight or ten days of the description of [OE]rsted’s discovery before the Academy of Sciences of Paris, enriched this field by a sudden burst of new discoveries and experiments. To Ampère we are indebted for our knowledge of the action of electric currents one upon another. For instance, if I suspend two flat coils in the presence of each other, it is easy to send an electric current in the same direction through both. The consequence of that would be an immediate attraction of the two coils for each other. It would be also easy to send currents in opposite directions, and the immediate consequence of that would be repulsion. If, having sent an electric current through one of these coils, a magnet is brought to bear upon it, the coil and the magnet interact almost like two magnets. The great law established by Ampère was that currents flowing in the same direction attract each other, whilst currents flowing in opposite directions repel each other. To show the interaction of magnets and currents, and to illustrate the simulation, if I may use the term, of magnetism by electricity, Ampère, by an extremely ingenious device, suspended spiral wires, and proved that when an electric current is sent through such a wire, it behaves, to all intents and purposes, like a magnet; it will set like a magnetic needle in the magnetic meridian. It was Ampère who first of all established the interaction of electric currents amongst themselves, and also between electric currents and magnets.
“Arago was engaged at the same time in joint work with Ampère. Perhaps one or two further illustrations might be given. Here we have a piece of copper wire. At the present moment there is no action whatever of that wire upon iron filings; the copper wire has no magnetic power whatever. But I send what for want of a better name, we call an electric current, through the wire, and then the iron filings crowd round the wire. If I break the circuit, the magic entirely disappears. This is one of the effects that enables us to see that a current is passing through the wire. Arago, who noticed this, went further and showed that, when you coil a wire round a piece of iron, the piece of iron is rendered strongly magnetic by the passage of the current through the wire.”
It is, however, as an experimentalist that Professor Tyndall excels, especially in illustrating by experiments the effects of electricity and magnetism. He was the first to show publicly the elongation of a solid bar of iron by magnetising it. He had a small mirror so connected with the end of a bar of iron two feet long that it reflected a long beam of light on a screen, and the beam moved on the screen as the bar of iron was lengthened or shortened. When the iron was magnetised by electricity from a battery the mirror showed a lengthening movement on the screen; and he explained that the bar being composed of irregular crystalline granules, the magnetism tended to set the longest dimensions of the granules lengthwise, or parallel to the flow of the current. Mr. Joule who discovered this lengthening effect of magnetism, found that a bar of soft iron was by this means extended one 720,000th of its length; and in later years Professor Hughes demonstrated the mechanical theory of magnetism, which, like the mechanical theory of heat, attributes such phenomena to a simple mechanical motion of the molecules of matter. Numerous researches and experiments led him to the conclusion that each molecule of a piece of iron, as well as the atoms of all matter, solid, liquid, and gaseous, is a separate and independent magnet, that each molecule can be rotated upon its axis by magnetism and electricity, and that the inherent polarity or magnetism of each molecule is a constant quantity like gravity.
Professor Tyndall also exhibited, both at the Royal Institution and at the Royal Society, Faraday’s marvellous experiment showing the magnetisation of light, which he described as Faraday’s third great discovery, and compared “to the Weisshorn among mountains—high, beautiful, and alone.” In a dark room a ray of light from a lamp passed between the poles of a large horse-shoe, and appeared as a spot of light on a screen. When by connecting a battery with the horse-shoe, the latter became powerfully magnetic, the spot of light was instantly moved on the screen, being visibly deflected by the magnetism of the horse-shoe.
To illustrate the velocity of the electric current he showed that a spark sent through a copper wire which passed through some gunpowder, did not ignite the gunpowder, because it had not time; but when a wet string—a slower conductor—was substituted for the copper wire, the passage of the current was retarded and the powder ignited. Another illustration of an accidental character he frequently narrated. While lecturing to an audience of young and old people at the Royal Institution, he caused fifteen Leyden jars to be charged with electricity, and by some awkwardness his shoulder touched the conductor leading from the jars. “I am extremely sensitive to electricity,” he said, “yet a charge from such a powerful battery as fifteen jars seemed to have no disastrous effect upon me. I stood perfectly still, wondering that I did not feel it; but I knew something had occurred; and after standing for a moment or two I seemed to open my eyes, which probably were open all the time. I saw a confused mass of apparatus about me. I felt it necessary to reassure the people before me, so I said: ‘Over and over again I have wanted that battery to be discharged into me, and now I have had it.’ Although I appeared unaffected, really the optic nerve in me was so affected that I saw my arm severed from my body. I soon, however, recovered proper sight, and saw that I was all right.” The explanation given for his intellect being thus clear while his vision was distorted, is that the electric current moved with much greater rapidity than the nervous agency by which the consciousness of pain is excited. According to Professor Bois-Reymond, the latter moves at the rate of ninety-eight feet per second, while, according to Professor Wheatstone, electricity moves in a copper wire at the rate of 288,000 miles per second. Hence it is probable that death by electricity or lightning is painless.
In a course of lectures delivered to a juvenile audience in December, 1884, he gave a fresh illustration of the ease with which electricity can be generated in a rather unusual way. It is stated in text-books on electricity that if a man could be suspended between the poles of a common magnet, he would point equatorially, because all the substances of which he is made are diamagnetic. Professor Tyndall, however, showed how easily his body could be made to act the part of a magnet. In the presence of his audience, a man repeatedly struck the back of the Professor’s coat with a piece of catskin, and in a minute or two sufficient electricity was generated to make his hand, held out in front of him, magnetic and capable of attracting to it different objects, just as a small magnet attracts bits of iron near it. He stated that this experiment had never, so far as he knew, been performed before.
In other lectures he illustrated the resistance of a telegraph cable to the transmission of the electric current over a length of 14,000 miles, by introducing into the path of the current gaps containing feebly conducting liquids, so distributed as to represent intervals equal to those in telegraphing between Gibraltar, Malta, Suez, Aden, Bombay, Calcutta, Rangoon, Singapore, Java, and Australia. Connected with these gaps were mirrors which cast ten dots of light on a large screen, being one for each gap or station; when the electric current was sent through the miniature cable, it so deflected a needle attached to each mirror as to cause dot after dot to start aside upon the screen. The interval between the movement of each dot of light exactly represented the time which the electric current would require to reach the several stations named in the working of a real cable. He thus strikingly illustrated the fact that the resistance of a cable depends in some degree upon its length, and visibly showed the time consumed in overcoming that resistance. To show the different resistances of different metals and how resistance produces heat, he took pieces of platinum and silver, and arranging them alternately in a long line, sent an electric current through them. Thereupon each piece of platinum, being a metal of great resisting power, glowed with a brilliant red heat, while the intervening pieces of silver, being good conductors, were invisible.
In 1878 he was exhibiting and explaining to a Parliamentary Committee the electrical effects produced in working by hand a dynamo machine, when Lord Lindsay asked, as “an elementary question,” what was the source of the mechanical power by which he was able to turn the wheel of the dynamo. The Professor explained that it was simply the combustion of the fat and tissues of his muscle. “Then will you explain,” said Lord Lindsay, “how it is that as the temperature of your muscle and your blood is only 100°, you get it up to fuse a wire which would require a temperature of 3,500°.” To that the Professor replied: “I would give all that I possess to be able fully to answer that question; but this much is absolutely certain, that all the heat developed in that dynamo, amounting to between 3,000° and 4,000° Fahr., is certainly derived from the combustion of my muscle. It is nothing more mysterious than the combustion of zinc in the voltaic battery.”
The facility with which he extemporises illustrations to make science entertaining appears from the following incident. “On one occasion,” he says, “I paid a visit to a large school in the country, and was asked by the principal to give a lesson to one of the classes. I agreed to do so provided he would let me have the youngest boys in his school. To this he willingly assented; and after casting about in my mind as to what could be said to the little fellows, I went to a village hard by and bought a quantity of sugar-candy. This was my only teaching apparatus. When the time for assembling the class had arrived I began by describing the way in which sugar-candy and other artificial crystals were formed, and tried to place vividly before their young minds the architectural process by which the crystals were built up. They listened to me with the most eager interest. I examined the crystal before them, and when they found that in a certain direction it could be split into thin laminæ with shining surfaces of cleavage, their joy was at its height. They had no notion that the thing they had been crunching and sucking all their lives embraced so many hidden points of beauty.” That incident occurred many years ago; and as illustrating his own perennial admiration of the phenomena of crystallisation another incident may be added that occurred in a lecture delivered in the Royal Institution in 1855. He was exhibiting the effect of applying an electric current by means of two wires to acetate of lead—vinegar and lead. The mixture becoming decomposed, the atoms of water appeared, when magnified and reflected on a large screen, as beautiful rings moving up and down the one wire, while the atoms of lead on the other wire formed themselves by crystalline action into pretty fern-like leaves and plants of all shapes and sizes. “Is not that beautiful?” said the Professor; “I have seen it done a hundred times, but I can never see it without wonder.”
Professor Tyndall has seen the triumph of several scientific principles of which he was one of the earliest and foremost advocates. Thus in 1884 he said: “With regard to the theory of evolution, I cannot help noting the wide toleration which has been infused into the public mind since the appearance of Mr. Darwin’s Origin of Species in 1858. Well do I remember the cry of anguish and detestation with which the views of Mr. Darwin were assailed when they were first enunciated. To one example of this I will here refer. There was a meeting of the British Association at Oxford in 1860, when the subject of the origin of species was discussed by the late Bishop Wilberforce. I was at a distance from the platform, my neighbours being for the most part clergymen. The vehemence with which the Bishop’s powerful sarcasm was cheered was extraordinary; and knowing full well that he would be effectually answered by a friend of mine, I was not able to forecast the consequences. But whatever these might be I was determined to share them; so I gradually edged my way through the crowd, overturning in my passage a seat on which many people were standing, till I got close to my friends, who, I feared, incurred some risk of a physical mauling. But the discussion passed away without violence, and in virtue of that plasticity with which the human mind in the long run takes the stamp of truth, those who were then so perturbed in spirit are now ready to admit, not only that the origin of species did them no particular harm, but that they are quite prepared to accept its doctrine.” On the occasion in question the Bishop of Oxford stated that the greatest names in science were then opposed to the Darwinian theory, which was chiefly defended by Professor Huxley and Dr. Hooker.
In like manner Professor Tyndall was able to say in 1885 that the germ theory of infectious diseases had grown like a mustard tree in his time. “I remember,” he said, “the time when it was referred to as an extravagant absurdity, but far-seeing men saw its final triumph. Now I suppose there is hardly a scientific physician in Europe that does not hold the germ theory of disease. In 1873 cases came before me of men suffering from intermittent or relapsing fever, and I longed to examine their blood; for it is a small spiral-looking organism in the blood that is the cause of relapsing fever. In 1876 Professor Cohn, of Breslau, was in this country, and he handed me a memoir that marks an epoch in the history of the subject with which it dealt. It was called in England the wool sorter’s disease, or splenic fever. It was sometimes also called Siberian plague. The paper had been drawn up from his own experiments and observations by a perfectly unknown physician, who held a small appointment in the neighbourhood of Breslau. The investigation impressed me as masterly in execution and as pregnant in result. The writer followed with the most unwearying patience and the most consummate skill, the life history of bacillus anthracis, which is the contagium of splenic fever. I said at the time this young man will soon find himself in a higher position, and next time I heard of him he was at the head of the Imperial Sanitary Institution of Berlin. That young man was Dr. Koch, who succeeded in detecting the living organism and in proving it to be beyond all doubt the veritable cause of the disease. Some years ago I paid a visit to a laboratory in Paris where I was shown by Pasteur himself, who verified Dr. Koch’s results as to the parasitic origin of splenic fever, this formidable bacillus anthracis, and it was curious to reflect how a thing so truly mean and contemptible should have such power over the lives of brutes and men.”
A report published in 1886 of examinations made by Dr. Miquel of the bacterial condition of the air at Paris and Mountsouris disclosed some remarkable facts. He stated that in the Rue de Rivoli the average number of bacteria in a cubic metre of air during the year 1881 was 6,295, whilst in 1884 the average number was only 1,830—a diminution which he attributed to the better draining and scavenging of the city. In the same period the deaths from zymotic disease in Paris showed a decrease of 27 per cent. The air over the Atlantic Ocean and on the top of high mountains showed only one to six bacteria per cubic metre. Such investigations are now recognised as a special department of science.
Some reminiscences which Professor Tyndall gave in 1880 of Thomas Carlyle showed his sympathetic appreciation of literary as well as scientific excellence. He exhibited the “sage of Chelsea” in a more favourable light than some of his literary friends have done. “It has been said that in respect to science Mr. Carlyle was not only incurious but hostile. This does not tally with my experience,” says Professor Tyndall. “During the lifetime of his wife and afterwards I frequently saw him, and as long as his powers continued unimpaired I do not remember a single visit in which he failed to make inquiries both regarding my own work and the general work of science. In physical subjects I never encountered a man of stronger grasp and deeper penetration than his. During my expositions, when these were clear, he was always in advance of me, anticipating and enunciating what I was about to say. He not unfrequently called to see me in Albemarle Street, and on such occasions I usually described to him what I was doing there. When I was engaged on the ‘chimera’ of spontaneous generation, I took him into my warm room, and explained to him the part played by the floating matter in the air in the phenomena of putrefaction and infection. He was profoundly interested, and as docile as a child.
“This, however, was not always his attitude. He sometimes laid down the law in matters where special study rendered my knowledge more accurate than his, and had in consequence to bear my dissent. Allow me to cite an illustration. In 1866 I accompanied him to Mentone, and by desire of his generous hostess stayed with him two or three days. One evening while returning from a drive the glow of sunset on sea and mountain suggested a question regarding the light. He stated his view with decision, while I unflinchingly demurred. He became dogmatic (‘arrogant’ is a word which can only be applied to Carlyle by those who never felt his influence) and invoked his old teachers, Playfair and Leslie, in support of his view. I was stubborn, and replied that though these were names meriting all honour, they were not authorities regarding the matter in hand. In short, I flatly and firmly opposed him; and it was not for the first time. He lapsed into silence, and we drove home. I went with him to his room. As he drew off his coat he looked at me mildly and earnestly, and pointing to an arm-chair, said in his rich Scotch accent, ‘I did not want to contradict you; sit down there and tell me all about it.’ I sat down, and beginning with the alphabet of the question, carried it as far as my knowledge reached. For more than an hour he listened to me, not only with unruffled patience, but with genuine interest. His questions were always pertinent, and his remarks often profound. I don’t know what Carlyle’s aptitude in the natural history of science might have been, but in regard to physics the contrast between him and Goethe was striking in the highest degree. His opinions had for the most part taken their final set before the theory of man’s descent was enunciated, or rather brought within the domain of true causes, by Mr. Darwin. For a time he abhorred the theory as tending to weaken that ethical element in man which, in Carlyle’s estimation as in that of others, transcends all science in importance. But a softening, if not a material, change of his views was to be noticed later on. To my own knowledge he approved cordially of certain writings in which Mr. Darwin’s views were vigorously advocated, while a personal interview with the great naturalist caused him to say afterwards that Charles Darwin was a most charming man.”
Of Carlyle’s own disposition, Professor Tyndall gives a more generous estimate than the public have been led to form since his death. “Knowing,” he says, “the depth of Carlyle’s tenderness, I should almost feel it to be bathos to cite the cases known to me which illustrated it. I call to mind his behaviour towards some blind singers in the streets of Marseilles, and the interest he took in the history of a little boy, whom, during my momentary separation from him, he had found lying in the shade of a tree, and over whose limbs paralysis was slowly creeping. There was a kind of radiance in the sorrow depicted in the old man’s face, as he listened to the tale and probably looked to woes beyond. The self-same radiance I saw for the last time as he lay upon his sofa, and for some minutes raised his head upon my shoulder a few weeks before his death.”
Professor Tyndall succeeded Faraday not only as Professor of the Royal Institution, but also as Scientific Adviser to the Trinity House, a position which he also regarded as one of honour on account of its associations with his distinguished predecessor. He has stated that, “When, in 1836, Professor Faraday accepted the post of Scientific Adviser to the Trinity House, he was careful to tell the Deputy Master that he did not do so for hire. ‘In consequence,’ he says, ‘of the goodwill and confidence of all around me, I can at any moment convert my time into money.’ In my little book on Faraday, published in 1868, I have stated that he had but to will it to raise his income in 1832 to 5,000l. a year. In 1836 the sum might have been doubled. Yet this son of a blacksmith, this journeyman bookbinder, with his proud and sensitive soul, rejecting the splendid opportunities open to him—refusing even to think them splendid in presence of his higher aims—cheerfully accepted from the Trinity House a pittance of 200l. a year. And when, in 1866, his mind, worn down in the service of his country and of mankind, was no longer able to deal with lighthouse work, I accepted his position, on terms not less independent than his own. I had no need to play the part of a candidate. The late able and energetic Deputy Master of the Trinity House, Sir Frederick Arrow, came to the Royal Institution, where, in courteous and indeed apologetic terms, he asked me to accept the post. I say apologetic, because, inasmuch as it was desired to continue Faraday’s salary to the end of his life, 100l. a year was all that could for the moment be offered to me. I set the mind of the Deputy Master at rest by expressing my willingness, for the sake of my illustrious friend, to do the work for no salary at all. In due time the larger income became mine, and later on, the scope of my duties being extended by the Board of Trade, my salary was raised from 200l. to 400l. a year. With this I was entirely content. Still, the chances open to a man of my reputation in physical science have not diminished since Faraday’s time; on the contrary, they have indefinitely increased. No person of understanding in such matters will doubt me when I say that had I gone in for consultations and experiments on commercial and technical matters, I could with ease have converted every hundred rendered to me by the Trinity House and Board of Trade into a thousand. And if I chose the lesser sum instead of its tenfold multiple, it was because I deemed its source to be one of peculiar honour, and the work it involved a work of peculiar beneficence.”
The Elder Brethren of the Trinity House have control of the lighthouses, lightships, beacons, and buoys around the United Kingdom; and some difference that arose as to a new invention for lighthouse illumination led to the retirement of Professor Tyndall from the position of Scientific Adviser to that body in May, 1883. The incident gave rise to an animated, not to say acrimonious, correspondence in the press, in the course of which the Professor stated that, “the head and front of my offending was my effort to protect from official extinction an able and meritorious man, who had the misfortune to raise a rival at the Trinity House, and to ruffle the dignity of the gentlemen of the Board of Trade. Struggling single-handed, relying solely on his own industry and talents, and with no public funds to fall back upon at pleasure, Mr. John Wigham, to whom I refer, during the brief period of his permitted activity, had made advances in the art of lighthouse illumination which placed him far ahead of all competitors. This man I did my best to protect from the effects of professional jealousy and bureaucratic irritation. It was my earnest desire to utilise Mr. Wigham’s genius for the public good. It was the object of officials whom he had offended to extinguish him. They did what they could to weary him and worry him and take the heart of enterprise out of him, and they certainly succeeded in checking the development of his system of lighthouse illumination. Had it not been for an opposition which, considering the interests at stake, seemed to me at times criminal, that system would assuredly be far more advanced than it now is. His rival was encouraged to push forward, while he was held back. The boldest attempt made against Mr. Wigham was the appropriation of his invention of superposed lenses for the new Eddystone lighthouse. This high-handed proceeding would have provoked litigation, had not the Elder Brethren, reverting to their more generous instincts, lately taken a more reasonable course than that which they were at one time advised to pursue. A compensation of 2,500l. was offered to Mr. Wigham, and eventually accepted by him.”
It thus appears that the independence of mind and chivalrous defence of scientific merit which characterised his early career were displayed with undiminished vigour and self-denial in later years, when the mellowing influences of age and the sunshine of popularity would have induced minds of a more flexible fibre to yield complacently to self-interest and power.
FOOTNOTES:
[5] Mr. Alfred Davis, after paying his composition of sixty guineas as a member of the Institution and three annual donations of twenty guineas for the promotion of research, at his death in 1870 bequeathed £2,000 for the same purpose. His deafness prevented him deriving any benefit from the lectures.
PROFESSOR WHEATSTONE.
CHAPTER I.
“Talent may follow and improve; emulation and industry may polish and refine; but genius alone can break those barriers that restrain the throng of mankind in the common track of life.”—Roscoe.
The saying is as old as Lucretius that time by degrees suggests every discovery, and skill evolves it into the regions of light and celebrity; thus in the various arts we see different inventions proceed from different minds, until they reach the highest point of excellence. The electric telegraph is sometimes mentioned as one of the latest illustrations of this theory of evolution. One of its first inventors, Steinheil, defined telegraphic communication, in its most general sense, as the method employed by one individual to render himself intelligible to others; and regarding it in that light as synonymous with intercourse, declared that it was no human discovery, but one of the most wonderful gifts of nature. In man, he said, this gift of nature has attained an astonishing development in the form of speech and writing; and as writing redeems the passing sounds from fleeting time, so in like manner are the remotest distances to be annihilated and thoughts to be interchanged with those far away; “the means of accomplishing this do not lie directly within our reach, but by patient observance of the powers and the phenomena of nature, we render these subservient to us and make them the bearers of our thoughts; and it is this task which in the ordinary acceptation of the word is termed telegraphic communication.” Such was the philosophic view of the nature of the electric telegraph propounded by Steinheil in 1838 when it was in nonage, and later writers have not hesitated to say that the idea of using the transmission of electricity to communicate signals is so obvious as hardly to deserve the name of an invention. But the fact is that this “idea” was in existence for two centuries before it could be turned to good account, because the one thing wanting in order to utilise it was an invention.
In 1617, Strada, in one of his prolusions published at Rome, mentioned the possibility of one friend communicating with another at a great distance by means of a loadstone so influencing a needle on a dial containing the letters of the alphabet as to make it point to the letters intended to form the communication. The same idea was recorded in 1669 by Sir Thomas Browne, who stated that this conceit was widespread throughout the world, and that credulous and vulgar auditors readily believed it, while the more judicious and distinctive heads did not altogether reject it. “The conceit,” he said, “is excellent, and if the effect would follow, somewhat divine: it is pretended that from the sympathy of two needles touched with the same loadstone and placed in the centre of two rings with letters described round about them, one friend keeping one and another the other, and agreeing upon the hour wherein they will communicate, at what distance of place soever, when one needle shall be removed unto another letter, the other, by wonderful sympathy, will move unto the same.” Dr. Johnson, in his Life of Sir Thomas Browne, says that “he appears indeed to have been willing to pay labour for truth. Having heard a flying rumour of sympathetic needles, by which, suspended over a circular alphabet, distant friends or lovers might correspond, he procured two such alphabets to be made, touched his needles with the same magnet, and placed them upon proper spindles; the result was that when he moved one of his needles, the other, instead of taking by sympathy the same direction, ‘stood like the pillars of Hercules.’ That it continued motionless will be easily believed; and most men would have been content to believe it without the labour of so hopeless an experiment.”
The prevalence of this “idea” on the Continent is shown by the following passage which appeared in a book of Mathematical Recreations by Schwenter, published in 1660:
“If Claudius were at Paris and Johannes at Rome, and one wished to convey some information to the other, each must be provided with a magnetic needle so strongly touched with the magnet that it may be able to move the other from Rome to Paris. Now suppose that Johannes and Claudius had each a compass divided into an alphabet according to the number of letters, and always communicating with each other at six o’clock in the evening; then (after the needle had turned round three and a half times from the sign which Claudius had given to Johannes), if Claudius wished to say to Johannes—‘Come to me,’ he might make his needle stand still, or move it till it came to c, then to o, then to m, and so forth. If now the needle of Johannes’ compass moved at the same time to the same letters, he could easily write down the words of Claudius and understand his meaning. This is a pretty invention; but I do not believe a magnet of such power could be found in the world.”
Addison, in the Spectator of 1711, called attention to the “idea” of Strada, and like Dr. Johnson spoke of it as a chimera. It thus appears that the two greatest intellects in England in the eighteenth century, the former adorning its opening and the latter its closing years, treated with supreme contempt the “idea” that intelligence could be communicated to a distance by magnetised needles pointing to the letters of the alphabet on a dial. Yet in the next century this “idea” became an accomplished fact, and Charles Wheatstone did more than any other man to make it an every day occurrence. Hence his name in England has been most prominently associated with the invention of the electric telegraph. Many able men had tried to solve the problem before him, but had not succeeded. Yet that which our wisest forefathers regarded as chimerical, and scientists of different nations laboured for in vain, we are now told was so obvious and simple as scarcely to deserve the name of an invention.
The electric telegraph claims a long pedigree. One of the first attempts to transmit signals through a wire by means of electricity was made in 1727 by Stephen Gray, a pensioner of the Charterhouse. He connected a glass tube with the end of a wire 700 feet long, and by rubbing the tube the wire became so electrified as to attract light bodies at the other end. He also discovered that a wire loop should not be used to fasten up his conductor, because such a loop not being an insulator the electricity escapes through it. His observations were written down by the Secretary to the Royal Society the day before his death. He stated that “there may be found a way to collect a greater quantity of electrical fire, and consequently to increase the force of that power, which by several of these experiments seems to be of the same nature with that of thunder and lightning.” Similar experiments were made a few years afterwards by Winkler of Leipsig, Lemonnier of Paris, and Watson in London, Franklin at Philadelphia, and De Luc at the Lake of Geneva.
In 1753 a definite scheme of telegraphic communication was published. In the Scots Magazine for February appeared a letter from a Renfrew correspondent, who signed himself C. M., on “An Expeditious Method of Conveying Intelligence.” This writer said: “Let a set of wires equal in number to the letters of the alphabet be extended horizontally between two given places; at the end of these wires let balls be suspended against a glass sheet, and the wires striking the glass, these balls would drop upon an alphabet arranged upon the table, and thus by a spelling method, communication could be made of words.”
In a book published in 1792, Mr. Arthur Young, who travelled in France in 1787, stated that “a very ingenious and inventive mechanic,” M. Lomond, had made a remarkable discovery in electricity: “You write two or three words on a paper; he takes it with him into a room and turns a machine inclosed in a cylindrical case, at the top of which is an electrometer, a small fine pith ball; a wire connects with a similar cylinder and electrometer in a distant apartment; and his wife by remarking the corresponding motions of the ball, writes down the words they indicate; from which it appears that he has formed an alphabet of motions. As the length of the wire makes no difference in the effect, a correspondence might be carried on at any distance. Whatever the use may be, the invention is beautiful.”
Twenty years after the publication of the letter of C.M. in the Scots Magazine, Le Sage of Geneva endeavoured to work a telegraph by means of twenty-four wires with a pair of pith balls attached to each, thus representing the letters of the alphabet. By the use of frictional electricity any of the balls at one end of the wire could be moved by the operator at the other end, but it was found difficult to get the balls after being electrified to resume their respective places. To overcome this difficulty, and also to produce the requisite number of signals with fewer wires, experiments were afterwards made by different men on the Continent, and notably by Ronalds in England. This experimenter erected a wire eight miles long in his garden at Hammersmith, and laboured for seven years to solve the problem of telegraphy with frictional electricity. He used a dial containing letters and figures, and the collapsing or diverging of a pith ball was to correspond with the desired letter. He offered this telegraph to the Government, who informed him in reply, that “telegraphs of any kind are now wholly useless, and no other than the one now in use will be adopted.” In a book which he wrote in 1823 he described a complete system of telegraph, and expressed the hope that he would see the day when the King at Brighton would be able to communicate by telegraph with his ministers in London. Both his plan and his book were neglected, but his wishes for the success of the telegraph were abundantly fulfilled. In 1874 Mr. Gladstone conferred on him the honour of knighthood in recognition of his early efforts in connection with the telegraph. He died shortly afterwards at the patriarchal age of ninety-one.
The discovery of the Voltaic pile, described in a previous chapter, gave a fresh impulse to electricians, and eventually supplied the requisite kind of electricity for working a practical telegraph. So great was the sensation excited among the learned by the discovery of the Voltaic pile, that in 1801 Napoleon called Volta from Pavia to Paris, and attended a meeting of the Institute to hear the theory of the pile explained by its discoverer. There and then Napoleon caused a gold medal to be voted to Volta, and afterwards gave him a valuable present of money. Indeed it is said that the pile excited the enthusiasm of Napoleon more than any other scientific discovery. Volta was made a member of the French Institute in 1802, and in the same year was born the man whose name was destined to be for ever associated with one of the most useful applications of Voltaic electricity—the electric telegraph.
Charles Wheatstone was born at Gloucester in February 1802. His father was a music-seller in that town; and on removing afterwards to London he became a teacher of the flute, and was accustomed to boast that he had been engaged in connection with the musical education of the Princess Charlotte. His son, Charles, was educated at a private school in his native city. It is said that he early showed an aptitude for mathematics and physics; but not much is known of his youthful career. On his removal to London he became a manufacturer of musical instruments, the scientific principles of which formed with him the subject of profound studies. His practical ingenuity was displayed in the application of the scientific principles he discovered to new purposes, to the construction of philosophical toys and the improvement of musical instruments. “In 1823,” says a friend of his who wrote a notice of him in the Proceedings of the Royal Society, “at the age of twenty-one, we find him in conjunction with his brother, long since deceased, engaged in the manufacture and sale of musical instruments in London.” But there is unquestionable evidence of his having obtained distinction in London by his ingenuity at the age of nineteen.
Of his first notable achievement in London the following curious account was given in September, 1821, in the leading literary journal of that time: “We have been much gratified,” said the writer, “with an exhibition in Pall Mall of an instrument under the denomination of the enchanted lyre, the invention of a Mr. Wheatstone. The exhibition room presents a work of handsome construction in the form of an ancient lyre suspended from the ceiling. Its horns terminate in mouths resembling bugles. Its centre is covered on both sides with plates of a bright metallic lustre, and there is an ornamented keyhole, like that of a timepiece, which admits of its being wound up, but which is evidently a mere ruse, as the instrument certainly does not utter melodious sounds in consequence of that operation. Round it there is a slight hoop-rail, perhaps five feet in diameter, which is supported by equally slight fixtures in the floor. The inventor disclaims mechanism altogether (though he winds up the machine) and asserts that the performance of the enchanted lyre is entirely the result of a new combination of powers. Be that as it may, its execution is both brilliant and beautiful. The music seems to proceed from it; the tones are very sweet; the expression soft or powerful, and the whole really charming. We listened to Steibelt’s battle-piece with unfeigned pleasure, and were equally delighted with several other compositions of simple melody and of more difficult harmony. Mr. Wheatstone professes to be able to give a concert, producing by the same means an imitation of various wind and stringed instruments; the lovers of music will have a treat in hearing the enchanted lyre go through a half hour’s entertainment.”
Another contemporary account is more prescient, if not amusing. On the 1st of September, 1821, it was reported in the Repository of Arts that “Under the appellation of the enchanted lyre Mr. Wheatstone has opened an exhibition at his music shop in Pall Mall, which has excited considerable sensation among the votaries of the art. The form of a lyre of large dimensions is suspended from the ceiling apparently by a cord of the thickness of a goose-quill. The lyre has no strings or wires, but these are represented by a set of metal or steel rods, and it is surrounded by a small fence. The company being assembled, Mr. Wheatstone applies a key to a small aperture, and gives a few turns representative of the act of winding up, and music is instantly heard, and apparently from the belly of the lyre. The sceptical he invites to stoop under the fence, and hold their ears close to the belly of the lyre; and they, including ourselves, are compelled to admit that the sound appears to be within the instrument; but while making this admission, the attentive auditor is instantly convinced that the music is not the effect of mechanism (a fact indeed which Mr. Wheatstone not only concedes, but openly avows, even in his notice). It is quite obvious that the music is produced by a skilful player, or perhaps two, upon one or more instruments. The music seems to proceed from a combination of harp, pianoforte, and dulcimer; it certainly at times partakes of the character of these three instruments; and in point of tone, the difference sometimes is considerably in favour of the lyre; the piano and forte appear more marked, the crescendo is extremely effective, and the forte in the lower notes is inconceivably powerful in vibration. The performance lasts an hour: various pieces of difficult execution are played with precision, rapidity, and proper expression.”
“It is evident that some acoustical illusion, effected through a secret channel of some sort or other, is the cause of our hearing the sound in the belly of the lyre.... How then is sound thus conducted so as to deceive completely our sense of hearing? This seems to be the only question that can suggest itself on witnessing this singular experiment; it is a secret upon which Mr. Wheatstone rests the interest and merit of this invention; and to this question, no one, as far as we can learn, has yet been able to return an answer that could solve every difficulty. It is really a very ingenious invention, which the proprietor as yet wishes to keep a secret. It may be proper to add that Mr. Wheatstone represents the present exhibition to be an application of a general principle for conducting sound, which principle he professes himself to be capable of carrying to a much greater extent. According to his statement, it is equally applicable to wind instruments; and the same means by which the sound is conducted into the lyre will, when employed on a larger scale, enable him to convey in a similar manner the combined strains of a whole orchestra. This promised extension of the principle of conducting musical sounds from one place to another gives rise to some curious reflections on the progress which our age is constantly making in discoveries and contrivances of every description. Who knows but by this means the music of an opera performed at the King’s Theatre may ere long be simultaneously enjoyed at Hanover Square Rooms, the City of London Tavern, and even at the Horns Tavern at Kennington, the sound travelling, like gas, through snug conductors, from the main laboratory of harmony in the Haymarket to distant parts of the metropolis; with this advantage, that in its progress it is not subject to any diminution? What a prospect for the art, to have music ‘laid on’ at probably one-tenth the expense of what we can get it ourselves! And if music be capable of being thus conducted, perhaps words of speech may be susceptible of the same means of propagation. The eloquence of counsel, the debates in Parliament, instead of being read the next day only—But we really shall lose ourselves in the pursuit of this curious subject.”
It has been said that the death of mystery is the grave of interest. Nevertheless, Charles Wheatstone did not keep secret the means by which this mysterious music was produced. In 1823 he contributed a paper to Thomson’s Annals of Philosophy in which he described the remarkably simple and original experiments that led him to the invention of this apparatus, and explained how molecular vibrations produced sound. With reference to phonic vibrations in linear conductors he said: “In my first experiments on this subject I placed a tuning-fork at the extremity of a glass or metallic rod five feet in length communicating with a sounding-board. The sound was heard as instantly as when the fork was in immediate contact, and it immediately ceased when the rod was removed from the sounding-board or the fork from the rod. From this it is evident that vibrations inaudible in their transmission, being multiplied by meeting with a sonorous body, become very sensibly heard. Pursuing my investigations on this subject, I discovered means of transmitting, through rods of much greater length, and of very inconsiderable thickness, the sounds of all musical instruments dependent on the vibrations of solid bodies and of many descriptions of wind instruments. One of the practical applications of this discovery has been exhibited in London for about two years under the appellation of the ‘Enchanted Lyre.’ So perfect was the illusion in this instance from the intense vibratory state of the reciprocating instrument and from the interception of the sounds of the distant exciting one, that it was universally imagined to be one of the highest efforts of ingenuity in musical mechanism.” It is a noteworthy evidence of the interest evoked by this article that it was reproduced in the leading French and German publications of that year.
This “Enchanted Lyre” has since been described by Mr. W. H. Preece as the first telephone. It was exhibited, he says, “to delighted crowds at the Adelaide Gallery; it was often used by Prof. Faraday, and has frequently since been produced by Prof. Tyndall at the Royal Institution. A large special box was placed in one of the cellars of the Institution, and a light rod of deal rested upon it. No sound was heard in the theatre until a light tray or other sounding-box was placed on the rod, whereupon its music pealed forth over the whole place. The vibrations of the musical box, with all their complexity and beauty, are imparted to the rod of wood and are thence given up to the sounding-box. The sounding-box impresses them upon the air, and the air conveys them to the ear, whence they are transmitted to the brain, imparting those agreeable sensations called music.”
Wheatstone’s invention of the Enchanted Lyre or the “first telephone” was no accidental discovery or lucky idea: it was the result of a profound and original investigation of the scientific principles of sound. He discovered and demonstrated by numerous experiments that sound was produced by the vibrations of the atmosphere; and in 1823 when he announced for the first time that “the loudness of sound is dependent on the excursions of the vibrations, volume or fulness of sound on the number of the coexciting particles put in motion,” he stated that he had just seen Fresnel’s paper, in which the same conclusions were arrived at with respect to light as he (Wheatstone) had proved with respect to sound. He added that “the important discoveries of Dr. Thos. Young have recently re-established the vibratory theory of light, and new facts are every day augmenting its probability. The new views in acoustical science which I have opened will, I presume, give additional confirmation to the opinions of these eminent philosophers.” Prophetic words!
The analogy between sound and light as results of wave-motions in air or ether is now part of the alphabet of science. Charles Wheatstone made an independent discovery of the principles of sound; but in this he was partly anticipated by Young. Nor was he alone in the original and practical experiments by which he demonstrated their accuracy. At the time he made these experiments (he was then only twenty years old), he thought he was the first who had indicated the phenomena of sound in that way; but Professor Oerstead, of Copenhagen, on seeing him perform these experiments, informed him of some similar ones he had previously made.
In the middle of the year 1827 he invented a small instrument consisting of a steel rod on the top of which a glass silvered bead was placed. By concentrating on it an intense light and making the rod to vibrate, beautiful forms were created. In this respect this philosophical toy resembled the Kaleidoscope which Brewster invented; and it was therefore called the kaleidophone. There is, however, no similarity between the construction or mode of action of the two instruments. In 1828 he devised the terpsiphone which made music by the reciprocal vibrations of columns of air. In 1833 he contributed to the Royal Society a paper on acoustic or Chladni figures, so called because Chladni in 1787 showed that by strewing sand on vibrating surfaces, and then throwing the particles into vibration by means of a violin bow, beautiful and varied symmetrical figures could be produced. Wheatstone showed that all the figures of vibrating surfaces result from very simple modes of vibration, oscillating isochronously, and superposed upon each other, the figures varying with the component modes of vibration, the number of the superpositions, and the angles at which they are superposed.
As indicating the variety of subjects that engaged his attention about the same time, a fact recorded by a friend may be quoted here. At one period Wheatstone’s attention was for a time directed to problems of mental philosophy, and especially to the quasi-mechanical solution of them which was hoped for by the followers of Gall and Spurzheim; he was an active member of the London Phrenological Society, then presided over by Dr. Elliotson, and in January 1832 he read a paper at one of the meetings on dreaming and somnambulism, which was published in extenso in the Lancet of that date. This paper is remarkable like all his writings for the extreme clearness with which known facts are stated and the deductions based upon them.
Another subject which occupied his attention for some years was the construction of speaking-machines, upon which he made certain improvements, and of which he wrote a short and interesting history. He declared in 1837 that the advantages which would result from the completion of a speaking-machine rendered the subject worthy of the attention of philosophers and mechanicians; and he endorsed a remark of Sir D. Brewster that before another century was complete a talking and singing machine would doubtless be numbered among the conquests of science.
In a paper which he communicated to the Journal of the Royal Institution in 1831 “On the Transmission of Musical Sounds through solid Linear conductors and on their subsequent Reciprocation,” he gave an account of some experiments that evolved a principle now found to be next in importance to that of the telegraph. He said: “I believe that previous to the experiments which I commenced in 1820, none had been made on the transmission of the modulated sounds of musical instruments, nor had it been shown that sonorous undulations, propagated through solid linear conductors of considerable length, were capable of exciting in surfaces with which they were in connection a quantity of vibratory motion sufficient to be powerfully audible when communicated through the air. The first experiments of this kind which I made were publicly exhibited in 1821; and on June 30th, 1823, a paper of mine was read by M. Arago at the Academy of Sciences, in which I mentioned these experiments, and a variety of others relating to the passage of sound through rectilinear and bent conductors. I propose in the present instance to give a more complete detail of these experiments.” He then proceeds to give an account of the experiments he had made during the intervening ten years, and concludes by saying: “As the velocity of sound is much greater in solid substances than in air, it is not improbable that the transmission of sound through solid conductors, and its subsequent reciprocation, may hereafter be applied to many useful purposes. Sound travels through the air at the rate of 1,142 feet in a second of time, but it is communicated through iron, wire, glass, or wood with a velocity of about 18,000 feet per second, so that it would travel a distance of 200 miles in less than a minute.... Should any conducting substance be rendered perfectly equal in density so as to allow the undulations to proceed with uniform velocity without any interference, it would be easy to transmit sounds through such conductors from Aberdeen to London, as it is now to communicate from one chamber to another. The transmission to distant places of a multiplication of musical performances are objects of far less importance than the conveyance of the articulations of speech. I have found by experiment that all these articulations, as well as the musical inflections of the voice, may be perfectly, though feebly, transmitted to any of the previously described reciprocating instruments, by connecting the conductor either immediately with some part of the neck or head contiguous to the larynx, or with a sounding-board, to which the mouth of the singer or speaker is closely applied.” Nearly half a century elapsed before these observations found their full application in the telephone and microphone.
It may be here noted that in a paper on experiments in audition published in 1827 Wheatstone said: “The great intensity with which sound is transmitted by solid rods at the same time that its diffusion is prevented, affords a ready means of augmenting the loudness of external sounds and of constructing an instrument which, from its rendering audible the weakest sounds, may with propriety be named the microphone.” It is said that that was the first time the word microphone was ever used; and it was the name given in 1878 to an instrument which has since come into general use as the complement of the telephone, the microphone being the best adapted for sending spoken messages by electric wire, and the telephone the best for receiving them.
Concurrently with these scientific studies, his practical powers as an inventor were being advantageously exercised in the improvement of musical instruments, old and new. In a communication to the Royal Institution in February, 1828, he gave an account of a Javanese musical instrument called the Génder, which was brought to England by the late Sir S. Raffles, and in which “the resonances of unisonant columns of air” were used to augment the sounds of the vibrations of metallic plates. A hollow bamboo of a certain length was placed perpendicularly under each metallic plate which, being struck and made to vibrate, produced a deep, rich tone by the resonance of the column of air within the bamboo. He then stated that, though other rude Asiatic and African instruments made use of the same principle, he did not know of its being used in any European instrument; and he therefore promised to publish soon an account of several methods which he had devised for utilising the resonance of columns of air. About two months afterwards his attention was called to a newly-invented German instrument which made use of that principle. It was called the Mund Harmonica; and, as the name implies, music was produced in it by placing the mouth over some small metallic tongues or springs and blowing upon them so as to cause them to vibrate; “these vibrations produced so many impulses upon the current of air and thus caused sound.” This instrument is now best known as a child’s toy. It was soon improved in Germany into a primitive kind of accordion, in which keys were placed over the metallic tongues, and the requisite current of air to vibrate them when the keys were opened was produced by compressing a kind of bellows, which formed the body of the instrument. This was the most simple form of wind instrument; and Charles Wheatstone soon increased its range and facilitated its manipulation. His improvements consisted in the employment of two parallel rows of finger studs or keys on each end, and in so placing them with respect to their distances and positions as that they might, singly, be progressively and alternately touched or pressed down by the first or second fingers of each hand without the fingers interfering with the adjacent studs, and yet be placed so near together as that any two adjacent studs might be simultaneously pressed down when required by the same finger; the peculiarity and novelty of this arrangement consisted in this, that whereas in the ordinary keyed wind musical instrument then in use the fingering was effected by a motion sideways of the hands and fingers, in the new arrangement that mode of fingering was rendered entirely inapplicable: and he made available a motion not previously employed, namely, the ascending and descending motions of the fingers. By this method of arranging the studs he was able to bring the keys much nearer together than had been done previously, and the instrument was made more portable. He also introduced two additional rows of finger studs on each end of the instrument for the purpose of introducing semitones when required. In other words, he invented the concertina, the first patent for which was dated June 19th, 1829, under the title of improvements in the construction of wind-musical instruments.
The accordion, (said to have been invented at Vienna by Damian in 1829,) is described by the best musical authorities as little more than a toy in comparison with the concertina. Indeed, the concertina is one of the few musical instruments distinguished for sweetness and compass, that is known to be the exclusive invention of one man. Music intended for the oboe, flute, and violin, can be played on it; while the only other instruments upon which music written for the concertina can be played, are the organ and harmonium. Nothing, says Dr. Grove, but the last-named instruments can produce at once the extended harmonies, the sostenuto and the staccato combined, of which the concertina is capable. The origin of the organ is lost in the myths of antiquity, and it has been the subject of improvements during the last 500 years. The harmonium is an evolution of the present century, and has been brought to its present state by the combined improvements of several musical men, including Charles Wheatstone. But of the concertina he was the sole inventor; and if it be true that the unknown man (or rather men) who invented the fiddle was a greater genius than the inventor of the steam-engine, surely the invention of the concertina was no mean achievement. Certainly it was not an instant achievement. Its perfection appeared to be a work of time; for in 1844 he took out another patent for improvements, consisting of (1) the arrangement of the touches or finger-stops which regulate the opening of the various valves covering the apertures in which the springs or tongues vibrate; (2) a mode of obtaining a different degree of loudness for each side of the concertina independently by applying a partition to divide the bellows into two parts; (3) a mode of arranging and constructing the cavities in which the tongues or spirals are placed, by which a bass concertina may be made of more portable dimensions than by the mode of arrangement usually adopted in the treble concertina; (4) a mode of constructing concertinas whereby the same tone or spring is made to sound whether the wind be driven into or out of the bellows, namely, by means of a double passage valve applied to each tongue separately; (5) a mode of varying at pleasure the pitch of the concertina by apparatus capable of altering the effective length of its tongues or springs; (6) an arrangement of the lever or support of the key or apparatus for admitting the wind to act upon the tongue of the concertina; (7) a mode of applying apparatus to sting a tongue or spring into vibration in addition to the wind on that tongue; and (8) of modifying or ameliorating the tone of a freely vibrating tongue or spring by means of the resonance of a column of air in a tube tuned in unison with it, the tube being so placed that the free air shall intervene between its open end and the tongue or spring.
In connection with this subject, it should be added that he made important improvements in the harmonium when it might be said to be in its infancy. Without going into details, suffice it to say that at the Great Exhibition of 1851 he exhibited the portable harmonium, which the jury on musical instruments described as quite original in all its mechanical parts. It had a compass of five octaves, and although the keyboard was of the same extent as in the larger harmoniums, the instrument could be instantly folded up so as to occupy less than half its height and length. The jury, in awarding the inventor a prize medal, said the portable harmonium was peculiarly constructed for producing expression, and might either be used by itself for the performance of music written for the organ or harmonium, or for taking violin, flute, or violoncello solos or parts—its capabilities of expression giving it great advantages in imitating these instruments.
In 1834 he was appointed Professor of Experimental Physics in King’s College, London; and as such he delivered in the following year a course of eight lectures on Sound; but while retaining the professorship, he soon discontinued lecturing because of his invincible distrust of his own powers as a speaker.
About the same time he gave to the world what, in order of time, might be described as the first fruits of his studies in electricity, and what, in point of originality, many electricians have described as his most brilliant discovery. In 1831 Professor Faraday told the Royal Institution of the method by which the silent philosopher proposed to ascertain the velocity of the electric spark; and in 1834 he himself contributed to the Philosophical Transactions “An account of some experiments to measure the velocity of electricity and the duration of the electric light.” It has been repeatedly said that this one experiment was enough to render his name immortal in the annals of science. The velocity of electricity is so great that it was believed there was no means on earth capable of measuring it. This desideratum Professor Wheatstone supplied. He devised means by which a small mirror was made to revolve at the immensely rapid rate of 800 times in a second, and in front of it placed half a mile of insulated copper wire, on the ends and in the middle of which were fixed brass balls intended to interrupt a current of electricity sent through the wire. On connecting the ends of the wire with a Leyden jar, he saw three sparks—one was at each end as the electricity left the jar, the other was at the brass balls in the middle of the wire. The one end of the wire was connected with the inner coating of the jar charged with positive electricity, while the other end of the wire was attached to the outer coating, which had negative electricity, so that at the moment of contact the electricity passed from each end of the wire in order to find an equilibrium. The middle of the wire, however, was cut, and had a small brass ball at each end, distant one-tenth of an inch; and when the two currents of electricity reached that interruption the middle spark was produced. These sparks were reflected by the rapidly revolving mirror; and he had the wire so arranged that if the three sparks were simultaneous, the mirror would show them in parallel straight lines. But they evidently were not simultaneous, for the middle one appeared a little later than the other two; the revolving mirror had in the interval moved round a minute distance, thus showing the reflection of the middle spark behind the others. The interval between the sparks was found to be the one millionth part of a second, and their appearance on the mirror, as it revolved, supplied data as to the rate at which the current moved, from which it was easily calculated that the velocity of electricity is 288,000 miles a second. Thus, it was said, he forced the lightning to tell how fast it was going. This experiment, which was originally made in his lecture-room at King’s College, and with the result of which he was much delighted, instantly spread his name throughout the civilised world as the discoverer of one of Nature’s greatest secrets.[6] The original apparatus used for that purpose was also used at the Royal Institution in 1856, to illustrate the instantaneous duration of a spark. It was ascertained that the duration of a spark does not exceed the twenty-fifth thousandth part of a second; it was explained that a cannon ball, if illuminated in its flight by a flash of lightning, would, in consequence of the momentary duration of the light, appear to be stationary; and that even the wings of an insect moving 10,000 times in a second would seem at rest.
With regard to the scientific value of the revolving mirror, M. Dumas said in 1875: “This admirable method enabled Arago to trace with a certain hand the plan of a fundamental experiment which should decide whether light is a body emanating from the sun and stars, or the undulating movement excited by them. Executed by the accomplished experimentalist, it proved that the theory of emission was wrong. This method has then furnished to the philosophy of the sciences the certain basis on which rest our ideas of the nature of force, and especially that of light. By means of this or some other analogous artifice, we can even measure the speed of light by experiments purely terrestrial, which, pursued by an able physicist, have guided the measure of distance between the earth and the sun.”
Professor Wheatstone himself suggested that the velocity of light might be measured in the same way as electricity. In July, 1835, he told the Royal Society that he proposed to extend his experiments on the velocity of electricity to measure the velocity of light in its passage through a limited portion of the terrestrial atmosphere. It may be added that the complete solution of the velocity of light by the revolving mirror, although the subject of elaborate experiments by Arago, was facilitated by some improvements made in the apparatus by later experimenters.
The mirror has been used in different ways for the measurement of light. In 1850, Arago gave a description of his attempts to determine its velocity, but failing eyesight prevented him carrying out his full design. The subject was, however, taken up by M. Fizeau and M. Foucault, who employed steam power instead of clockwork to give motion to the mirror. By Foucault’s method a beam of light was reflected from a revolving mirror to a fixed concave mirror, and before it was reflected back again the revolving mirror had moved a sufficient space to enable him to compute therefrom the velocity of light. Fizeau’s method was simpler. He made a toothed wheel revolve with great rapidity, while a beam of light passed through one of the open spaces between the teeth, and fell upon a reflecting mirror at a considerable distance away. If the wheel were at rest, the beam would be reflected back through the same space by which it had entered; but the wheel being in rapid motion, the reflected beam would either fall on the next tooth which would prevent it passing through, or if the motion were increased, it would get through the next opening. A variety of tests like these has given the velocity of light as about 187,000 miles per second.
Professor Wheatstone also rendered memorable service in connection with the development of spectrum analysis. In a paper which he communicated to the Dublin meeting of the British Association in 1835, on “The Prismatic Analysis of Electric Light,” he expounded a discovery which has since led to useful results. Most metals, such as iron, copper, and platinum, when exposed to the gas flame, impart no colour; for that purpose they must be subjected to a higher temperature; and Professor Wheatstone found that the best way of attaining the requisite temperature was by the use of the electric spark. He found that a single electric discharge passed through a gold wire at once dissipated the metal into vapour. He also showed that by looking through a prism at the spark proceeding from two metallic poles, the spectra seen contained bright lines which differed according to the kind of metal employed. “These differences,” he said, “are so obvious that any one metal may instantly be distinguished from others by the appearance of its spark, and we have here a mode of discriminating metallic bodies more ready than chemical examination, and which may hereafter be employed for useful purposes.” Hofmann has well said that “within this fact a new mode of distinguishing bodies from each other lay folded, like the tree within the seed, awaiting evolution. The new line of research thus opened by Wheatstone with reference to bright lines produced by electric discharges, was pursued in a variety of directions by several observers. Foucault (1849), Masson (1851-55), Angström (1853), Alter (1854-55), Secchi (1855), Plückar (1858-59), Bunsen and Kirchhoff (1860), were successively engaged in this inquiry. It would exceed the limits of this sketch to minutely describe the phenomena presented by the spectra of the known metals, or to dwell on the infinitely minute quantities of substances found to be capable of producing the effect. The extreme delicacy of the new process is now a familiar fact; and it is equally well known that in using this method, the presence of one metal scarcely interferes with that of another. It would be out of place here to do more than simply mention the astronomical applications of spectrum analysis; such as, for example, the determination by its means of the composition of the solar atmosphere, in which M. Kirchhoff has proved, with a degree of probability approaching to certainty, the presence of several metals well known on this earth; amongst others potassium, sodium, calcium, iron, nickel, chromium, &c.” This delicate test has made it possible to detect the presence of the two hundred millionth part of a grain (in weight) of sodium, while by revealing bright lines not referable to any known body it has been the means of discovering five new metals—cæsium and rubidium by Professor Bunsen in 1860, thallium by Mr. Crookes in 1861, indium by Professors Richter and Reich in 1864, and gallium by M. Lecoq in 1875.
The year 1836 was distinguished in the history of electricity by the discovery of the constant battery of Professor Daniell. Early in that year Professor Daniell, of King’s College, announced in a letter to Faraday, that he had been led to the construction of a voltaic arrangement which furnished a constant current of electricity for any length of time, and had thus been able to remove one of the greatest difficulties which had hitherto obstructed those who had endeavoured to measure and compare different voltaic phenomena. This constant battery, which he improved in the spring of the same year, is still in general use. In it the zinc is placed in a semi-saturated solution of sulphate of zinc, and the copper in a saturated solution of sulphate of copper, the two solutions being separated by a porous earthenware partition. This battery furnishes a constant supply of electricity for weeks together.
Early in 1837 Professor Wheatstone publicly called attention to the capability of the thermo-electric pile as a source of electricity. Seebeck of Berlin discovered in 1822 that when different metals are soldered together and their junction heated, a current of electricity is generated; and Nobili and Melloni contrived on that principle the thermo-multiplier, an apparatus which indicates the effects of heat by the deflections of a needle on a scale, like a thermometer, the needle being moved by the electricity produced by the heat. But this means of producing electricity was better known for its delicacy than for its strength till Professor Wheatstone made some experiments—probably the first made in England—for the purpose of showing how the thermo-electric pile could be utilised as a source of electricity. In his account of these experiments he stated that “the Cav. Antinori, director of the Museum at Florence, having heard that Professor Linari, of the University of Siena, had succeeded in obtaining the electric spark from the torpedo by means of an electro-dynamic helix and a temporary magnet, conceived that a spark might be obtained by applying the same means to a thermo-electric pile. Appealing to experiments, his anticipations were fully realised. No account of the original investigations of Antinori had reached England in April, 1837; but Professor Linari, to whom he early communicated the results, published certain experiments and observations of his own on the subject in L’Indicatore Sanese for December 13, 1836.” The interesting nature of these experiments induced Professor Wheatstone to attempt to verify the principal results. For that purpose he used a thermo-electric pile consisting of 33 elements of bismuth and antimony formed into a cylindrical bundle ¾ of an inch in diameter, and 1⅕ in length. The poles of this pile were connected by means of two thick wires with a spiral of copper ribbon 50 feet in length and 1½ inch broad, the coils being well insulated by brown paper and silk. One face of the pile was heated by means of a red-hot iron brought within a short distance of it, and the other face was kept cool by contact with ice. Two short wires formed the communication between the poles of the pile and the spiral, and the contact was broken, when required, in a cup of mercury (a non-conductor) between one extremity of the spiral and one of these wires. Whenever contact was thus broken a small but distinct spark was seen. He added that Professors Daniell, Henry, and Bache assisted in the experiments, and were all equally satisfied of the reality of the appearance. At another trial the spark was obtained from the same spiral connected with a small pile of fifty elements, on which occasion Dr. Faraday and Professor Johnson were present, and verified the fact. By connecting two such piles together, so that similar poles of each were connected with the same wire, the spark was seen still brighter. He concluded by stating that such experiments supplied a link that was wanting in the chain of experimental evidence tending to prove that electricity, from sources however varied, is similar in its nature and in its effects; and that the effect thus obtained from the electric current originating in the thermo-electric pile might no doubt be easily exalted by those who had the requisite apparatus at their disposal, till it equalled the effect of an ordinary voltaic pile.
As Professor Wheatstone was not accustomed to write articles or to deliver lectures, it is not an easy matter to measure the extent of his knowledge at any particular time; but one more incident may be mentioned as indicating the range of his studies on electricity about this time. Between 1830 and 1835 William Snow Harris wrote several articles in the Nautical Magazine on the utility of fixing lightning conductors in ships. It was a popular impression then that pointed metal rods attracted lightning. Snow Harris contended, on the contrary, that damage to ships occurred not where good conductors were, but where they were not, and that such conductors could no more attract lightning than a watercourse could be said to attract water, which necessarily flowed through it at the time of heavy rains. He afterwards prepared a list of 220 ships of the British Navy which were struck and damaged by lightning between 1792 and 1846. In June, 1839, a committee of the Admiralty consulted Professor Wheatstone and Professor Faraday as to the safety of the continuous conductors advocated by Snow Harris. To that committee Professor Wheatstone stated that “it has been proved beyond all doubt that electricity follows the best conducting path which is open to it; and that when it finds a metallic road sufficient to conduct it completely, it never flies to surrounding bodies greatly inferior in conducting power. The experiments of M. de Romas, made in France, with the electrical kite, immediately after Franklin’s first attempt, might satisfy the most timid in this respect. Imagine, writes he to the Abbé Nollet, ‘that you see sheets of fire nine or ten feet long and an inch broad, which made as much or more noise than reports of a pistol. In less than an hour I had certainly thirty sheets of these dimensions, without counting a thousand others of seven feet and under. But what gives me the greatest satisfaction in this new spectacle is that the largest sheets were spontaneous, and notwithstanding the abundance of fire which formed them, they constantly followed the nearest conducting body. This constancy gave me so much security that I did not fear to excite this fire with my discharger, even when the storm was violent; and when the glass branches of the instrument were only two feet long I conducted wherever I pleased, without feeling the smallest shock in my hand, sheets of fire six or seven feet long, with the same facility as those of only six or seven inches.’ The wire of the kite was insulated, and the sparks were drawn by a metallic conductor held in the hand by means of an insulating handle, and communicating with the ground by a chain. The human body is known not to be one of the worst conductors; yet, because it was two feet further than a far more perfect one, it received none of the discharge, even though the conducting path were an interrupted one. The phenomenon to which the name of lateral explosion has been generally given was first observed by Henly, more than half a century ago, and has been subsequently experimented upon by Priestly, Cavallo, and more recently by Biot.” The committee attached the greatest weight to the opinion of Professor Wheatstone, which Faraday supported, and which was eventually adopted. Experiment and experience confirmed its accuracy.
At the time when he had attained such a recognised position as an electrician he was making progress in another field of electrical study in which he was destined to gain still greater eminence and to obtain more extensive and permanent results.
FOOTNOTES:
[6] The accuracy of Wheatstone’s experiment has been generally accepted; but, as Faraday said in 1838, “the velocity of discharge through the same wire may be greatly varied by circumstances.... If the two ends of the wire in Professor Wheatstone’s experiment were immediately connected with two large insulated metallic surfaces exposed to the air ... then the middle spark would be more retarded; and if these two plates were the inner and outer coating of a large jar, or a Leyden battery, then the retardation of that spark would be still greater.”
CHAPTER II.
“There is a certain meddlesome spirit which, in the garb of learned research, goes prying about the traces of history, casting down its monuments, and maiming and mutilating its fairest trophies. Care should be taken to vindicate great names from such pernicious erudition. It defeats one of the most salutary purposes of history, that of furnishing examples of what human genius and laudable enterprise may accomplish. For this reason some pains have been taken to trace the rise and progress of this grand idea (in the mind of Columbus); to show that it was the conception of his genius, quickened by the impulse of his age, and aided by those scattered gleams of knowledge, which fell ineffectually upon ordinary minds.”—Washington Irving.
In all the inventions and discoveries previously described as made by Professor Wheatstone, his originality has never been seriously challenged, but when we turn to his greatest work we enter upon contested ground. The contests that ever arise as to the origin of great inventions afford evidence of their greatness; for, as Aeschylus says, he who is not envied is not worthy of admiration.
“In 1435,” says Sir James Mackintosh, “a law suit was carried on at Strasburg between one John Guttenberg, a gentleman of Mentz, celebrated for mechanical ingenuity, and Drizehn, a burgher of the city, who was his partner in a copying press. No litigation could seem more base and mechanical to the barbarous Barons of Suabia and Alsace; but the copying machine was the printing press which has changed the condition of mankind.” In like manner it fell to the lot of Professor Wheatstone when he had completed his most useful invention to have his originality disputed by his own partner in business, Mr. William Fothergill Cooke. There are five mechanical inventions that have conferred incalculable benefit on the industrial world in modern times—the printing press, the steam engine, the electric telegraph, the dynamo, and the Bessemer process of steel making. The originality of every one of these has been either divided or disputed, with the single exception of the Bessemer process, which is therefore the only one that is universally known by the inventor’s name. In the case of the electric telegraph the originality or priority of Professor Wheatstone was disputed not only at home but abroad. Hence writers on the subject are accustomed to say that the telegraph was invented independently and almost simultaneously by Professor Wheatstone, of London, Professor Morse, of New York, and Professor Steinheil, of Munich. This was in the year 1837.
After the discovery of the voltaic pile, Oersted discovered in 1819 that if a needle were placed parallel to a conducting wire, an electric current from a voltaic battery applied to the wire would cause the deflection of the needle to a position at right angles to the wire or across the direction of the current. Ampère proposed to make an electric telegraph by utilising this property of a compass needle, and he designed an apparatus to which twenty-five wires were attached; and by touching keys which corresponded to the letters of the alphabet, needles attached to the other ends of the wires were set in motion by the action of an electric current. It was this incipient and very imperfect design that Professor Wheatstone brought to perfection by a series of inventions and discoveries extending over a number of years. His own account of the origin of his telegraph is candid and interesting. “When, in 1823,” he says, “I made my important discovery that sounds of all kinds might be transmitted perfectly and powerfully through solid wires and reproduced in distant places, I thought I had the most efficient and economical means of establishing telegraphic (or rather telephonic) communication between two remote points that could be thought of. My ideas respecting establishing a communication of this kind between London and Edinburgh you will find in the Journal of the Royal Institution for 1828. Experiments on a larger scale, however, showed me that the velocity of sound was not sufficient to overcome the resistance and enable it to be transmitted efficiently through long lengths of wire. I then turned my attention to the employment of electricity as the communicating agent; the experiments of Ronalds and others failed to produce any impression on the scientific world; this want of confidence resulted from the imperfect knowledge then possessed of the velocity and other properties of electricity; some philosophers made out a few miles per second; others considered it to be infinite; if the former were true, there would not be much room for hope; but if the velocity could be proved to be very great there would be encouragement to proceed. I undertook the inquiry, and with the result the whole scientific world is acquainted. At the same time I ascertained that magnetic needles might be deflected, water decomposed, induction sparks produced, &c., through greater lengths of wire than had yet been experimented upon. In the following year, at the request of the Royal Society, I repeated these experiments with several miles of insulated wire, and the results were witnessed by the most eminent philosophers of Europe and America. I ascertained experimentally (which had never been done before) many of the conditions necessary for the production of the various magnetic, mechanical, and chemical effects in very long circuits; and I devised a variety of instruments by which telegraphic communication should be realised on these principles.
“Some time before Mr. Cooke introduced himself to me I considered my experiments to be sufficiently matured to enable me to undertake some important practical results. I informed Mr. Fox, the engineer of the London and Birmingham Railway, of my expectations, and told him of my willingness to superintend the establishment of an electric telegraph on that railway. I had also made arrangements for trying an experiment across the Thames. Mr. Enderby kindly undertook to prepare the insulating rope containing the wires and to obtain permission from Mr. Walker to carry the other termination to his shot tower. After many experiments had been made with the rope, and the permission granted, I relinquished the experiment, because after my connection with Mr. Cooke it was necessary to divert the funds I had destined for this purpose to other uses. What I have stated above is sufficient to show that I had paid great attention to the subject of telegraphic communication by means of electricity, and had made important practical advances long before I had any acquaintance with or ever heard of Mr. Cooke.”
On reading this account two questions arise: first, whether the Wheatstone telegraph was the first of its kind; and, secondly, whether there is any corroborative evidence of the early labours of its inventor. These two questions at the time became interlinked in a singular way. In 1833 the celebrated scientists, Gauss and Weber, placed a line of wire from the Observatory of Göttingen University to a building a mile distant, and by sending magneto-electric currents through that wire they communicated intelligible signals; but as the needle they used weighed nearly a hundredweight they saw that their apparatus needed much improvement before it would be of practical utility. Being otherwise engaged themselves, they invited Professor Steinheil, of Munich, to construct an improved electric telegraph; and Steinheil, after much labour, succeeded in producing an apparatus capable of transmitting signals, but it was too refined for practical working with the means then available. His instrument for receiving and recording the signals consisted of two needles, one of which was to be moved by a positive and the other by a negative current, both currents being sent through one wire. Connected with each needle was a small reservoir of ink and a pen, which, on being depressed by the motion of the needle, marked a line upon a strip of paper that was drawn along by means of clockwork. At first he used a second wire for the return circuit, but in the course of his experiments he discovered that the earth was the best receiver of the return current, and accordingly dispensed with the second wire. Now, strange to say, the experiments connected with this telegraph of Steinheil’s became indirectly a circumstantial witness of Professor Wheatstone’s labours before ever he saw Mr. Cooke.
The number of the Magazine of Popular Science published on March 1st, 1837, contained “an account of some new experiments in electro-magnetism.” It was a description of the experiments of Gauss at Göttingen, communicated to the Munich Academy of Sciences by Prof. Steinheil, who, in concluding, stated that he himself “had fitted up a telegraph similar in principle to that which connected the Observatory and the Cabinet of Natural Philosophy at Göttingen. Signals made in the room appropriated to the magnetic observations were transmitted to another department at a considerable distance, whence the answers were returned to the first room. He had arranged this apparatus for the purpose of demonstrating the peculiarities and the practicability of Professor Gauss’s contrivance, hoping by these means to draw attention to it, and to induce persons to employ it for connecting stations far more distant than any to which it has yet been applied.” To that was added the following: “Note by Editor: During the month of June last year (1836), in a course of lectures delivered at King’s College, London, Professor Wheatstone repeated his experiments on the velocity of electricity, which were published in the Philosophical Transactions for 1834, but with an insulated circuit of copper wire, the length of which was now increased to nearly four miles; the thickness of the wire was 1/16th of an inch. When machine electricity was employed, an electrometer placed on any point of the circuit diverged, and wherever the continuity of the circuit was broken, very bright sparks were visible. With a voltaic, or with a magneto-electric machine, water was decomposed, the needle of a galvanometer deflected, &c., in the middle of the circuit. But, which has a more direct reference to the subject of our esteemed correspondent’s communication from Munich, Professor Wheatstone gave a sketch of the means by which he proposes to convert his apparatus into an electric telegraph, which, by the aid of a few finger-stops, will instantaneously and distinctly convey communications between the most distant points. These experiments are, we understand, still in progress, and the apparatus, as it is at present constructed, is capable of conveying thirty simple signals, which, combined in various manners, will be fully sufficient for the purposes of telegraphic communication.”
These words must have been in type, and most probably were printed before the day on which Mr. Cooke said he first saw Professor Wheatstone; and they were certainly printed before the date fixed by Professor Wheatstone as the time of Mr. Cooke’s introduction to him. Professor Wheatstone says:
“I believe it was on the first day of March, 1837, that Mr. Cooke introduced himself to me. He told me that he had applied to Dr. Faraday and Dr. Roget for some information relative to the subject on which he was engaged, and that they had referred him to me. He gave me no clue as to the purpose he had in hand. I replied that he was welcome to all the information I could give him, and that the experiments I had been making for some time relative to employing electric currents for the purpose of telegraphic communication would enable me to give him much of the information he required. At our next interview shortly after, he told me he was working at an electric telegraph, and that the questions he had previously put to me related to this subject. After that I showed him some of my apparatus, and explained my proposals. Mr. Cooke showed me some of his drawings and models. I at once told him it could not act as a telegraph, and to convince him of the truth of this assertion I invited him to King’s College to see the repetition of my experiments. He came, and after seeing a variety of voltaic magnets, which even with powerful batteries exhibited only slight adhesive attraction, he expressed his disappointment in these words which I well remember: ‘Here is two years’ labour wasted.’
“With regard to Mr. Cooke’s invention, so far from its being practically useful, he has never, during my whole acquaintance with him, shown it to me in action, even in a short circuit. Mr. Cooke’s intention was, as he told me in the early stage of our acquaintance, to take out a patent for his invention. Mine was, when I had finished my experiments, to publish the results, and then to allow any person to carry them into effect. When Mr. Cooke found that his instrument was inapplicable to the purpose proposed, and that my researches were more likely to be practically useful, he proposed a partnership, and that we should take out a joint patent. The proposal did not proceed from me, and the sole reason of my acquiescing in the arrangement was that Mr. Cooke appeared to me to possess the zeal, ability, and perseverance necessary to make the thing successful as a commercial enterprise. I felt confident of overcoming myself all the scientific and mechanical difficulties of the subject, but neither my occupations nor my inclination qualified me for the part Mr. Cooke promised to perform. He said he was not wanting a scientific reputation, his sole object being to make money by it.
“The magnetic needle telegraph, as it appears in its most perfect state in the lecture room of the college, is to all intents and purposes entirely and exclusively my own invention. The original suggestion of Ampère (that a telegraph should be constructed by utilising the tendency of the magnetic needle always to place itself at right angles to an adjoining wire through which an electric current passed) was all that I borrowed in it. The most important point was my application of the theory of Ohm to telegraphic circuits, which enabled me to ascertain the best proportions between the length, thickness, and circumference of the multiplying coils and the other resistances in the circuit, and to determine the number and size of the elements of a battery to produce the maximum effect. With this law and its applications none of the persons who had before occupied themselves with experiments relating to electric telegraphs, had been acquainted.”
It may here be explained that Ohm was another eminent electrician, whose immortal discovery was at first consigned to neglect. His work, expounding the principle now known as Ohm’s law, was published at Berlin in 1827; but was not translated into English till 1841. It is said that for the first ten years after the publication of his work, only one continental author admitted or confirmed his views, but between 1836 and 1841, scientific men began to appreciate the value of his researches. Wheatstone was one of them. In 1841 Ohm was presented with the Copley gold medal of the Royal Society, when the President said: “Ohm has shown that the usual vague distinctions of intensity and quantity have no foundation, and that all the explanations derived from these considerations were perfectly erroneous. He has demonstrated both theoretically and experimentally that the action of a circuit is equal to the sum of the electromotive force (E. M. F.) divided by the sum of the resistances, and that whatever the nature of the current, whether voltaic or thermo-electric, if this quotient be equal, the effect is the same.”
Mr. George Cruikshank afterwards published a statement confirming the claims of Professor Wheatstone. He said that having been a friend of Professor Wheatstone, he wished to state that “the discovery of the telegraph arose from the circumstance that when first appointed lecturer at King’s College, he had seven miles of wire in the lower part of the building which abuts upon the river Thames, for the purpose of measuring the speed of lightning or the electric current. Upon one occasion when explaining his experiments to me, he said: ‘I intend one day to lay some of this wire across the bed of the Thames and to carry it up to the Shot Tower on the other side, and so to make signals.’ This was, I believe, the first idea or suggestion of a submarine telegraph. We are also indebted to him for the electric bell, for long before the telegraph came before the public, in explaining the machine to me, he said that as it was possible that one party might be asleep at one end of the wire, he had so arranged the working that the first touch should ring the bell at the other end, even if thousands of miles apart. This, it will be admitted, is an important part of the discovery.”
Next to the mechanism by which electric signals are made intelligible, one of the most important inventions is that by which an electric current is enabled to renew its strength as it goes along a great length of wire. The apparatus used for this purpose is called a relay, and the first man to publish an account of it was Prof. Wheatstone. Its mechanism is delicate and sometimes complex, but its principle can be easily understood. Most people understand that when a railway train has run a great distance, the engine requires to take in water or coal, and for that purpose it sometimes moves on to a siding in connection with which there is a constant supply of water or coal. In like manner, on long telegraphic lines electric batteries are kept in readiness at certain distances; but if they were connected with the main line it is obvious that their contents would be uselessly dissipated. They are therefore kept in a kind of siding, and are only temporarily connected with the main line for the purpose of replenishing a passing current. In the case of a railway the service of a pointsman is often needed to connect and disconnect a siding; but in the case of the telegraph the connecting link between the replenishing battery and the main line is made self acting. This is effected by the use of that property of electricity which causes an electrified wire to attract to it an adjacent piece of wire or iron. In the relay a needle or lever is so adjusted that when a feeble current comes along the main line, it attracts the needle of the relay line, and by means of this connection a fresh current from the local battery flows on to the line, and does the work which the original current had become too feeble to accomplish. This invention was embodied in the first patent of Professor Wheatstone; and Professor Henry, of New York, has sworn to the fact that when he was in London, in 1837, Professor Wheatstone showed him in King’s College, early in April, his method of bringing into action a second galvanic current by means of the deflection of a needle. Professor Bache was also present.
The first patent was taken out in June, 1837, in the joint names of Cooke and Wheatstone. Their telegraph had five wires and five needles. The guiding principle of their signalling apparatus was that a current of electricity on passing along a wire deflected the magnet or needle. Professor Wheatstone candidly acknowledged that he was not the discoverer of that principle; but it was he who discovered the practical basis upon which the wires and magnets should be adjusted so as to produce the desired effects. He arranged in a row five needles like those in a mariner’s compass; and when a current of electricity was sent along one of the wires the needle attached to it could be deflected to the right or left at the will of the sender. In the original form of the receiving instrument the needle was worked or deflected upon the face of a dial, upon which the letters of the alphabet were so arranged that any letter could be indicated at will by the sender making two of the deflected needles converge towards the desired letter. Any person could manipulate this instrument, as there was no secrecy or code involved in its signals.
FACE OF WHEATSTONE’S FIRST TELEGRAPH INSTRUMENT.
A glance at the illustration will show the simplicity of this apparatus. The objection to it was that it required five wires to transmit the signals and a sixth wire to bring back the electricity after it had done its work. But the only other electric telegraph then announced in England required twenty-six wires; and it is in comparison with previous efforts that the first Wheatstone instrument should be judged. It is a curious fact that just fifty years after the invention of this instrument with six wires, a new system of telegraphing was tried by which six messages could be sent almost simultaneously on one wire, either all in one direction, or part of them in one direction and the remainder in the opposite direction.
The first electric telegraph designed by Wheatstone was laid down on the North Western Railway between Euston Square and Camden Town Stations, a distance of a mile and a half. It was first worked on the evening of July 25th, 1837, which may be considered as the birthday of the electric telegraph in England. Let us see how and where it came to pass. Late in the evening, in a dingy little room near the booking office at Euston Square, by the light of a flaring dip candle, which only illuminated the surrounding darkness, sat the inventor with a beating pulse and a heart full of hope. In an equally small room at Camden Town Station, where the wires terminated, sat Mr. Cooke, his co-partner, and among others two witnesses well known to fame, Mr. Charles Fox and Mr. Stephenson. These gentlemen listened to the first word spelled by that trembling tongue of steel, which will only cease to speak with the extinction of man himself. Mr. Cooke, in his turn touched the keys and returned the answer. “Never,” said Professor Wheatstone, “did I feel such a tumultuous sensation before, as when all alone in the still room I heard the needles click, and as I spelled the words I felt all the magnitude of the invention now proved to be practicable beyond cavil or dispute.”
Nevertheless the public treated it with indifference; the directors of the railway soon gave it notice to quit, and one of them even denounced it as “a new-fangled thing.”
The next line of telegraph was made on the Great Western Railway. In July, 1839, a line of wires was laid from Paddington to West Drayton, a distance of thirteen miles. An arrangement had been made between the Railway Company and Messrs. Cooke and Wheatstone to the effect that within a certain number of months after the telegraph had been laid and efficiently worked between these two places, the Railway Company might call on the patentees to give them a license for the whole of the line, and the Railway Company had the power to construct a telegraph all the way from Bristol to London for a certain number of years; but the work not being done within the prescribed time, the agreement became void, and for some time the telegraph did not extend beyond Slough—a distance of seventeen miles. From the first the line to West Drayton worked satisfactorily. For the purpose of testing whether it could be relied on, it was used for nearly two months to communicate to Paddington the moment of the passing of the trains at West Drayton and Hanwell, and it was found to answer admirably. The cost of making that line was from £250 to £300 a mile, including the charge for station instruments. At first the wires placed in a tube were put underground, but it was soon found better to have them above ground, where they were less liable to injury from wet.
Early in 1840 Professor Wheatstone claimed as the result of experience that thirty signals could be conveniently made in a minute by this telegraph, and at the same time he stated that “having lately occupied myself in carrying into effect numerous improvements which had suggested themselves to me, I have, in conjunction with Mr. Cooke, who has turned his attention greatly to the same subject, obtained a new patent for a telegraph which I think will present very great advantages over the present one. It can be applied without entailing any additional expense by simply substituting new instruments for the old ones. This new instrument requires only a single pair of wires to effect all that the present one does with five; so that three independent telegraphs may be immediately placed on the line of the Great Western. It presents in the same place all the letters of the alphabet according to the order of succession, and the apparatus is so extremely simple that any person, without any previous acquaintance with it, can send a communication and read the answer.”
When Professor Wheatstone made the above statement, he also explained that Mr. Cooke had devised an apparatus whereby a bell worked by one wire could be rung at the other end of the wire by the sender, in order to draw the attention of the receiver to the message about to be sent. He added that Mr. Cooke had particularly directed his attention to an arrangement by means of which communications could be made from intermediate parts of the line where there were no fixed stations. For that purpose posts were placed at every quarter of a mile along the line from which the guard of a train might, if necessary, send a message to a station in either direction by means of a portable instrument which he was to carry with him.
It was in the same year, after these statements were made, that Mr. Cooke began his series of complaints against Professor Wheatstone, whom he accused of claiming the invention of the telegraph as his exclusive work, and of omitting all mention of his (Mr. Cooke’s) name in connection with it. Mr. Cooke now (1840) maintained that he himself had invented the first telegraph, and thereupon a war of words arose as to the respective parts played by the patentees in the joint undertaking.
The controversy thus raised between the two partners, instead of being allowed to produce an instant rupture, which might have injured the progress of the telegraph, was submitted to the decision of Sir M. Isambard Brunel, engineer of the Thames Tunnel, and Professor Daniell, of King’s College, the one a friend of Mr. Cooke and the other a friend of Professor Wheatstone, and on April 27th, 1841, these two gentlemen drew up the following statement: “In March, 1836, Mr. Cooke, while engaged at Heidelberg in scientific pursuits, witnessed, for the first time, one of those well-known experiments with electricity considered as a possible means of communicating intelligence which have been tried and exhibited from time to time during many years by various philosophers. Struck with the vast importance of an instantaneous mode of communication to the railways then extending themselves over Great Britain as well as to Government and general purposes, and impressed with the strong conviction that so great an object might be practically attained by means of electricity, Mr. Cooke immediately directed his attention to the adaptation of electricity to a practical system of telegraphing, and giving up the profession in which he was engaged, he from that hour devoted himself exclusively to the realisation of that object. He came to England in April, 1836, to perfect his plans and instruments. In February, 1837, while engaged in completing a set of instruments for the intended experimental application of his telegraph to the tunnel of the Liverpool and Manchester Railway, he became acquainted, through the introduction of Dr. Roget, with Professor Wheatstone, who had for several years given much attention to the subject of transmitting intelligence by electricity, and had made several discoveries of the highest importance connected with this subject. Among these were his well-known determination of the velocity of electricity when passing through a metal wire; his experiments in which the deflection of magnetic needles, the decomposition of water, and other voltaic and magneto-electric effects were produced through greater lengths of wire than had ever before been experimented upon; and his original method of converting a few wires into a considerable number of circuits, so that they might transmit the greatest number of signals that can be transmitted by a given number of wires by the deflection of magnetic needles.
“In May, 1837, Messrs. Cooke and Wheatstone took out a joint English patent on a footing of equality for their existing inventions. The terms of their partnership, which were more exactly defined and confirmed in November, 1837, by a partnership deed, vested in Mr. Cooke as the originator of the undertaking the exclusive management of the invention in Great Britain, Ireland, and the Colonies, with the exclusive engineering department, as between themselves, and all the benefits arising from the laying down of the lines and the manufacture of the instruments. As partners standing on a perfect equality, Messrs. Cooke and Wheatstone were to divide equally all proceeds arising from the granting of licenses or from the sale of patent rights, a percentage being first payable to Mr. Cooke as manager. Professor Wheatstone retained an equal voice with Mr. Cooke in selecting and modifying the forms of the telegraphic instruments, and both parties pledged themselves to impart to each other for their equal and mutual benefit all improvements of whatever kind which they might become possessed of connected with the giving of signals or the sending of alarms by means of electricity. Since the formation of the partnership the undertaking has rapidly progressed under the constant and equally successful exertions of the parties in their distinct departments, till it has attained the character of a simple and practical system worked out scientifically on the sure basis of actual experience.
“While Mr. Cooke is entitled to stand alone as the gentleman to whom this country is indebted for having practically introduced and carried out the electric telegraph as a useful undertaking, promising to be a work of national importance; and Professor Wheatstone is acknowledged as the scientific man whose profound and successful researches had already prepared the public to receive it as a project capable of practical application; it is to the united labours of two gentlemen so well qualified for mutual assistance that we must attribute the rapid progress which this important invention has made during the five years that they have been associated.”
For a time the rivalry or jealousy seemed at rest. Both Mr. Cooke and Professor Wheatstone concurred in the above statement, and Mr. Cooke gave prominence to the portions of it most favourable to him, claiming that such passages formed the award of an arbitration that resulted in his favour. But Professor Daniell in 1843 explained that this document was not an “award” of the arbitrators, for the arbitration was not proceeded with. The arbitrators, considering the pecuniary interests at stake and the relative position of the parties, were of opinion, he said, that without entering into the evidence of the originality of the invention on either side, a statement of facts might be drawn up, of the principal of which there appeared to be no essential discrepancy in the statement of either party, and that they might thus amicably settle the unfortunate misunderstanding that had occurred. He added that with a view to promote such an amicable settlement the arbitrators insisted, as a preliminary step, upon the withdrawal and destruction of 1000 copies of an ex parte statement of evidence proposed to be brought forward, and of a most intemperate address prepared by Mr. Cooke’s solicitor.
The lull produced by that document was only temporary. When anything was published making favourable mention of Professor Wheatstone’s originality as the inventor of the telegraph, Mr. Cooke or his partisans openly accused the Professor of tampering with the press, and Mr. Cooke himself was not above publishing protestations for the purpose of showing his “own surprising forbearance,” as well as the “egotism,” “humiliation,” and “perseveringly repeated misrepresentations” of Professor Wheatstone!
In later years Mr. Cooke or his friends paraded before the public an article in his favour that appeared in a quarterly review since deceased. That article was represented as having been written by Sir David Brewster, and as giving a correct account of the origin of the telegraph. It stated that Mr. Cooke had previously held a commission in the Indian Army, “and having returned from India on leave of absence and on account of ill health, he afterwards resigned his commission and went to Heidelberg to study anatomy. In the month of March, 1836, Professor Möncke of Heidelberg exhibited an electro-telegraphic experiment in which electric currents, passing along a conducting wire, conveyed signals to a distant station by the deflection of the magnetic needle inclosed in Schweigger’s galvanometer or multiplier. The currents were produced by a voltaic battery placed at each end of the wire, and the apparatus was worked by moving the ends of the wires backward and forward between the battery and the galvanometer. Mr. Cooke was so struck with this experiment that he immediately resolved to apply it to purposes of higher utility than the illustration of a lecture, and he abandoned his anatomical pursuits and applied his whole energies to the invention of an electric telegraph. Within three weeks, in April, 1836, he made his first electric telegraph, partly at Heidelberg, and partly at Frankfort. It was of the galvanometer form consisting of six wires, forming three metallic circuits, and influencing three needles. By the combination of these, he obtained an alphabet of twenty-six signals. Mr. Cooke soon afterwards made another electric telegraph of a different construction. He had invented the detector, for discovering the locality of injuries done to the wires, the reciprocal communicator, and the alarm. All this was done in the months of March and April, 1836; and in June and July of the same year he recorded the details of his system in a manuscript pamphlet from which it was obvious that in July, 1836, he had wrought out his practical system from the minutest official details up to the records and extended ramifications of an important political and commercial engine.” The article goes on to say that when his telegraphic apparatus was completed, he showed it in November, 1836, to Mr. Faraday, and afterwards submitted it and his pamphlet in January, 1837, to the Liverpool and Manchester Railway Company, with whom he made a conditional arrangement, with the view of using it on the long tunnel at Liverpool. In February, 1837, when he was about to apply for a patent he consulted Mr. Faraday and Dr. Roget on the construction of the electro-magnet employed in a part of his apparatus, and the last of these gentlemen advised him to consult Professor Wheatstone, to whom he went, according to Mr. Cooke’s account, on the 27th of February, 1837.
Now the article containing these statements was doubtless attributed to Sir David Brewster in the hope that his name would be accepted as a guarantee of its accuracy. Fortunately for all concerned, however, Sir David Brewster had previously placed on record his opinion on this question of the telegraph in a manner that put it beyond doubt. Asked by a Committee of the House of Lords in 1851 whether Professor Wheatstone was the undoubted inventor of the electric telegraph, Sir David Brewster replied: “Undoubtedly he is.” Further asked whether there was not a Swede who had paid great attention to the subject, Sir David said Oersted was the discoverer of electromagnetism, but had that not been discovered at all, ordinary magnetism was quite capable of being the moving power in the electric telegraph. He added that if electromagnetism had been the only means of working a telegraph, then the merit, not of the telegraph, but of what was necessary to the existence of the telegraph, would have belonged to Professor Oersted. When, on the other hand, the same Committee pressed Sir I. K. Brunel to say whom he considered the inventor of the telegraph, he replied: “Messrs Cooke and Wheatstone derive a large sum of money from the electric telegraph; but I believe you will find fifty people who will say that they invented it also: I suppose it would be difficult to trace the original inventor of anything.”
It has never been denied, though often overlooked, that Mr. Cooke obtained his first idea of a telegraph from Professor Möncke of Heidelberg—a circumstance which detracts from its originality. But the matter did not rest there.
When Mr. (then Sir) W. F. Cooke died in 1879, Mr. Latimer Clark published the portion of his private correspondence which related to his first connection with Professor Wheatstone, and although Mr. Latimer Clark endeavoured to put everything in the light most favourable to Mr. Cooke, the letters of the latter in essential points confirm the case of Professor Wheatstone. For example, after writing numerous letters to his mother explaining that he was busy trying to make a telegraph, Mr. Cooke wrote on February 27th, 1837: “Dissatisfied with the results obtained, I this morning obtained Dr. Roget’s opinion, which was favourable but uncertain; next Dr. Faraday’s, who, though speaking positively as to the general results formerly, hesitated to give an opinion as to the galvanic fluid action on a voltaic magnet at a great distance when the question was put to him in that shape. I next tried Clark, a practical mechanician, who spoke positively in favour of my views, yet I felt less satisfied than ever, and called upon a Mr. Wheatstone, Professor of Chemistry at the London University, and repeated my inquiries. Imagine my satisfaction at hearing from him that he had four miles of wire in readiness, and imagine my dismay on hearing afterwards that he had been employed for months in the construction of a telegraph, and had actually invented two or three with the view of bringing them into practical use. We had a long conference, and I am to see his arrangement of wire to-morrow morning, &c.... The scientific men know little or nothing absolute on the subject. Wheatstone is the only man near the mark.” Mr. Latimer Clark accounts for the notice of Professor Wheatstone’s experiments in the Magazine of Popular Science for March, 1837, by saying that it was “evidently inserted after the remainder of the articles had been completed, and set in type,” and that Wheatstone supplied the information after Mr. Cooke’s visit to him—a gratuitous assertion which is not supported by any positive evidence. Then, again, Mr. Latimer Clark, an eminent authority upon the laws of electricity, says, concerning Mr. Cooke’s proposed telegraph, that “upon the whole the instrument, the result of such long cogitation and experiment, is disappointing, and one is not surprised at Wheatstone, with his exquisite mechanical appreciation, criticising it as severely as he did.” Moreover, he admits that the first telegraph instrument used between Camden Town and Euston was Wheatstone’s.
Not less emphatic or explicit was the statement of the case given by Professor Wheatstone himself, and moreover it contained some passages of biographical interest. Addressing Mr. Cooke, he said: “You state that you alone had succeeded in reducing to practical usefulness the electric telegraph at the time you sought my assistance. This I wholly deny. Your instrument had never been practically applied, and was incapable of being so. Mine were all founded on principles which I had previously proved by decisive experiments would produce the required effects at great distances. Your statement that I employed myself at your request in perfecting your invention in detail is equally erroneous. My time, so far as it was devoted to telegraphic researches, was exclusively occupied in perfecting my own instrument, which had nothing in common with yours, and in which I was not only known to be engaged by all my scientific friends, but which was even announced in public print before I knew of your existence. I confined myself to carrying out one of my own inventions for two reasons: First, because my experiments led me to believe that the motions of a needle could be produced at distances at which no effects of electro-magnetic attraction could be obtained; and, secondly, I did not wish to interfere with you. With regard to the subsequent development of my first telegraph, the essential principles of which are the formation of numerous circuits from a few wires and the indication of characters by the convergence of needles, I am indebted to no person whatever; it is in all its parts entirely and exclusively my own. The modifications you introduced without consulting me in the instruments for the Great Western Railway altered the simplicity and elegance of the arrangement without the slightest advantage, and I certainly should not recognise them in any published description.”
“The circumstances under which your name was allowed to take the lead in the titles of the British patents have escaped your memory. I will endeavour to recall them to you. When you first proposed partnership, you know how strongly I opposed it, and on what grounds. I said I was perfectly confident of being able to carry out my views to the end I anticipated, that I fully intended doing so, and publishing the results, then allowing any person to carry them into practical effect. I told you that, while I admired the ingenuity of your contrivance I deemed it inapplicable to the purpose proposed, and I urged that in that case the association of my name with that of others would diminish the credit I should obtain by separately publishing the result of my researches. You replied that you were not seeking scientific reputation, and therefore no difference could arise between us on that account, and that your sole object was to carry the project into profitable execution. A patent was arranged to be taken out in our joint names which should include our two separate instruments. When we met to settle the preliminaries for the English patent I was much surprised to find your name inserted first, considering that, as we put ourselves on an equality by each contributing an invention, to put my well-known name after yours, then totally unknown, might be construed into an admission of the superiority of your share. You urged that your pecuniary obligations were the greater, and that as I intended to leave negotiations with you, your authority might be less respected if your name appeared second, and that your invention was the more valuable—an assumption I did not admit, and the event proved I was right. But we agreed that in subsequent patents the order should alternate. Some time after we met to settle the Scotch patent draft, for which you had prepared the declaration. I was again surprised to find the same order of precedence repeated, and I objected to it as contrary to our previous understanding. You said it had been done without your knowledge, but objected to the alteration on the ground of delay. After discussion we made a new arrangement, that on my allowing your name to stand on the British patents, mine should take the lead in all foreign ones. It was resolved afterwards that an American patent should be obtained, and when I attended to sign the preliminary papers, I found that again, without any notice to me, my name was made to follow yours. I refused to sign the papers, and you then consented to keep your word. The only reason you alleged was that your authority as manager would be diminished if you appeared as second partner.
“When I had attained some complete results, I invited you to the College to see them, and before describing or showing the new experiments and instruments, I proposed conditions: That having, at my own expense, undertaken a series of investigations which led to important consequences greatly increasing the pecuniary value of the patents, and having invented new instruments which, besides being applicable to all the purposes for which the existing arrangements could be applied, might also be profitably applied to other purposes to which the previous instruments were not at all adapted, I required as a compensation that I should retain the exclusive right of manufacturing them and all instruments I should construct involving the same principles, and also the privilege of employing them exclusively for domestic and official purposes. To these conditions you assented, and afterwards I showed you the completed instruments, and read to you a list of the further experiments. You confirmed your assent. On this occasion you breathed not a word respecting the claim since put forward to be considered the joint inventor of my new instruments.
“You ask me to acknowledge that ‘I, having certain improvements on our joint invention in progress depending fundamentally upon principles first discovered and applied by you, had asked as a favour,’ &c. It is unjust to urge such an acknowledgment upon me, and I state plainly that nothing shall compel me to make it. My instruments are original combinations involving a great number of points entirely new. With equal justice Mr. Ronalds might call upon me to declare that he is the joint inventor, because, like him, I use a revolving dial with letters—or Professor Steinheil complain of my suppressing his name because, in one of my most recent important modifications I employ, as he has done, the magneto-electric machine—as you to put forth that claim, because in some of my new instruments I have employed magneto-electric attraction, which you had done before me in your instrument; or with the same reason might Mr. Morse call upon me to proclaim him to be joint inventor because he, independently of you, has employed an electro-magnet to move machinery intended for a telegraph. One of your complaints is, that in the notices of my experiments in Belgium the employment of two wires for an electric telegraph was not specifically mentioned as a discovery of yours. Such a claim on your part has no foundation, for, without going further back, Ronalds’ two telegraphs—two telegraphs on different principles, which I myself proposed before I knew you,—and Steinheil’s telegraph, with which I was acquainted before yours, had two wires. You forget that it is my electric telegraph, and not yours, that is in daily use. And, lastly, you forget that, had it not been for my exclusive attention to it since I first conceived the idea, a practical telegraph might still have remained an unaccomplished purpose.
“Do not, however, misunderstand me. Far be it from me to underrate your exertions; they have been very great, and absolutely indispensable to the success of our joint undertaking. Without your zeal and perseverance and practical skill, what has been done would not have been so readily effected; but on the other hand, I may say, that had you entered the field without me, your zeal, perseverance, and money would have been thrown away.”
His subsequent as well as his previous inventions afford the strongest evidence of his originality. His inventions were not more distinguished for ingenuity than for permanent usefulness, and they had this unusual characteristic, that nearly every one of them became the parent of a considerable offspring. These form his most enduring monument, and a simple record of them forms his best vindication.
In 1840 he produced three inventions at one birth—his dial telegraph, his printing telegraph, and his electric clock. Each of these instruments was worked by utilising one of the great discoveries previously made in electro-magnetism. It was known that when an electric current is sent through a wire coiled round a piece of soft iron, the iron becomes a magnet. If the current is stopped for a moment, the iron instantly ceases to act as a magnet. When the piece of iron is magnetic, it will attract another piece of iron, and as the attraction ceases as soon as the current ceases, the iron can then by means of a spring be made to resume its original position. Thus by frequently interrupting an electric current, a piece of iron held in its place by a small spring can be made to move to and fro as often as it is attracted. Professor Wheatstone invented a method of regulating the application of the current to such a magnet, and of converting the to-and-fro motion of the iron into symbols. The piece of mechanism that regulated the current was a wheel called a commutator or communicator; around its circumference were twenty-four teeth; and each tooth was made to act as a conductor of electricity in this way: Under the teeth of the communicator there was a metallic circle which was connected with the telegraph wire; and in this metallic circle twenty-four pieces of wood were inserted at equal distances apart; so that the teeth of the communicator, which was connected by wire with the battery, at one moment touched the conducting metal of the circle underneath it, and thus imparted a current to the telegraph wire, while at the next turn a pace round they rested on the non-conducting wood, by which the current was prevented from passing from the communicator wheel to the telegraph wire. In a complete revolution of such a wheel the current would be twenty-four times established and as often interrupted; and each of these twenty-four alternations was made to indicate a letter of the alphabet at the other end of the wire by means of a piece of mechanism like a clock. When the current passed along the wire, it electrified a magnet, which then drew towards it an armature (a piece of iron). The movement of this armature (forward by electricity and backward again by a spring) acted like a pendulum in moving a wheel, which in turn moved a hand on a dial containing the letters of the alphabet. Just as at each movement of the pendulum of a clock, a wheel moves one tooth forward; so at each movement of the armature by an electric current, a twenty-four toothed wheel was moved one tooth forward, and at each such movement the hand on the dial moved from one letter of the alphabet to the next one. If, for instance, the indicator hand stood at A and it was desired to transmit E, this would be done by moving the communicator wheel four teeth onward; in doing that four successive currents would be transmitted to the indicator, the hand of which would consequently move over B, C, D, and then reach E, where a pause would indicate that this was the letter intended to be read. This was called Wheatstone’s electro-magnetic telegraph, because it was worked by an electric current from a battery electrifying a magnet.
In 1841 he invented a machine in which magnets produced electricity sufficient to work the telegraph. Hence it was called a magneto-electric machine, and the telegraph worked by it was called a magneto-electric telegraph. In 1840 he explained that magneto-electricity was of momentary duration as contrasted with the continuous action of electro-magnetism. The magneto-electric machine then in use consisted of a coil or coils of insulated wire being made to revolve in the vicinity of a magnet, or the magnet revolving in the vicinity of the insulated coils of wire, and this apparatus only produced a series of shocks, or instantaneous as compared with continuous currents. His new invention combined several of these machines into one by so uniting their coils as to form one continuous circuit, thereby producing the same effect as a perfectly continuous current. He said this magneto-electric machine could be used for many purposes for which a voltaic battery had been employed. The patent for it was taken out in his own name.