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.