Heroes of science

by P. Martin Duncan

Many facts had been recorded regarding the ancient history of the earth, and a host of ideas, more or less absurd, had been given forth on geology, during the years which preceded and followed the reformation. Several Italian geologists had examined into the truths discovered by Pythagoras, and, as stated in the preceding pages, the nature of fossils had become understood by a few liberal minded men. The age of Newton, and the years which followed his time, were consumed, however, so far as the history of the earth was concerned, by vain attempts to form cosmogonies, to account for the origin of the globe and visible universe. There was also a fierce struggle between two great geological factions, one asserting that all rocks were the product of heat, and the other denying this in toto and deciding that water was the originator. Many, and indeed nearly all, geologists taught that nature had acted during the past, by fits and starts, and that great convulsions had occurred, bringing the earth at last to its present condition. The common sense of mankind was opposed to many of these beliefs, and there was moreover a very great indisposition, on the part of many educated men, to credit that the earth was more than six thousand years old. Not a few believed that the hills and dales, mountains and plains, cliffs and valleys, were first formed as they are now.

A Scottish gentleman, a quiet retiring man, having some means of his own, studied the structure of the rocks and taught himself physical geography. He mastered a great number of undoubted facts, and reasoned upon them, and produced a theory which made geology a science, instead of a jumble of guesses flavoured with the love of the marvellous.

James Hutton was the son of William Hutton, a merchant living in Edinburgh, and was born in that city on the 3rd of June, 1726. His father, a man highly respected for his good sense and integrity, and who had held the important office of city treasurer, died whilst the boy was young. The mother was a woman of considerable ability, and she determined that her child should have a good education. He went, consequently, to the High School, and subsequently was entered at the University at the early age of fourteen. James was a thorough student, and loved work, and his tastes were directed rather to natural science than to classics and the higher mathematics. He studied mathematics under Maclaurin, and used to say in after years that although he enjoyed Professor Stevenson’s teaching of logic, still he thought more of him because a hint that was given in a lecture led him to take a passionate interest in chemistry. The fact that gold is dissolved in aqua regia (a mixture of nitric and hydrochloric acids), and that two acids, which can each of them dissolve any of the baser metals, must unite their strength before they can attack the most precious, was mentioned by the professor, in illustration of some general doctrine. Hutton was much impressed with this fact, and was led to study it further, and he got all the books on the subject. This led to his love of chemistry, which never forsook him, and which really decided the course of his career. But Hutton was destined for a profession, and his mother did not intend him to occupy himself solely with science. Consequently he was articled to a writer to the signet, with a view of becoming a lawyer. He had hard work to do, and plenty of it; it was mere routine work, that of a clerk, and there was a possibility that he would forget his scientific pleasures. His desire for knowledge persisted, in spite of his monotonous work, and occasionally he endeavoured to teach his fellow clerks a little, and he was found amusing himself and them with chemical experiments, when he should have been copying papers or studying the forms of legal proceedings. His master soon saw that the young man’s mind was not that which would suit a lawyer, so, with much kindness and good sense, he released his young friend from his obligations. Young Hutton at once began to study medicine, as that science which was the most closely allied to chemistry. He attended lectures, and studied well from 1744 to 1747. Then, as the teaching at Edinburgh was not sufficient in all the parts of medical studies, he went, as was usual, to Paris, where he studied chemistry and anatomy with great ardour. He was there for nearly two years, and then went to Leyden, in Holland, where he took his degree in September, 1749. On his return to London at the end of that year, he began to think seriously about settling in the world. Edinburgh afforded no flattering prospect for his establishment as a physician. The business there was in the hands of a few eminent practitioners, who had been long established; so that no opening was left for a young man whose merit was yet unknown, who had no powerful connections to assist him on his first outset, and very little of that patient and circumspect activity by which a medical man pushes himself forward in the world.

Full of anxiety about the future, Hutton wrote to a friend of his own age on the subject. This was Mr. James Davie, with whom Hutton had been on most intimate terms before leaving Scotland. They had both a great love of chemistry, and had experimented together, especially on the nature and production of ammonia. Their experiments had led to some valuable discoveries, and had been pursued by Mr. Davie during his friend’s absence. They had afforded a reasonable expectation of establishing a profitable manufacture of some salt of ammonia from coal-soot. The project of this establishment was communicated by Mr. Davie to his friend, who was still in London, and it appears to have lessened his anxiety about settling as a physician, and, probably, was one of the main causes of his laying aside all thoughts of that profession. Perhaps, too, on a nearer view, he did not find that the practice of medicine would afford him that leisure for pursuing chemical and other scientific objects which he fancied it would do, when he saw things at a greater distance. In fact, Hutton found himself in the same position as many other men of genius who have pursued as successfully the peculiar studies requisite for an accomplished medical man. Anatomy, physiology, chemistry, and botany have often been much more attractive to the aspirant for medical fame than surgery, practical medicine, and the study of drugs and their uses. Many a good doctor has been spoiled by over-education, and science has gained an enthusiastic student. It would appear, however, that there was another cause which was influencing Hutton. He had inherited a little property in land in Berwickshire from his father; it was possible to live on it, and farm and work at chemistry without risk, whilst if he sold it, or used the rent in advancing his position as a medical man, he might fail after all.

Certain it is that he returned to Edinburgh, and in the summer of 1750 he abandoned his intention of practising, and resolved to apply himself to agriculture. He had as a friend Sir John Hall, of Dunglass, a man of ingenuity and taste for science, and also an agriculturist. As he was never destined to do anything by halves, Hutton determined to study farming in the school which was then reckoned the best, and the manner which is undoubtedly the most effectual. He went into Norfolk, and fixed his residence for some time in that county, living in the house of a farmer, who served both for his landlord and his instructor. This he did in 1752. He always spoke well of John Dybold, who made him comfortable, and whose practical lessons in husbandry he much valued. He appears, indeed, to have enjoyed this situation very much: the simple and plain character of the society with which he mingled, suited well with his own, and the peasants of Norfolk could find nothing in the stranger to set them at a distance from him, or to make them treat him with reserve. It was always true of Dr. Hutton that to an ordinary man he appeared to be an ordinary man; possessing a little more spirit and liveliness, perhaps, than it is usual to meet with. He enjoyed Norfolk life very much, and doubtless it was the very different soil of that county which made the young Scotchman think, for the first time, about the construction of the surface of the earth which he hoped to till and profit by. While his head quarters were thus established in Norfolk, he made journeys, on foot, into different parts of England; and though the main object of them was to obtain information in agriculture, yet he never passed a pit, or a cliff, or a river-side, without studying the structure of the soil, so that in 1753, Hutton was incontinently making himself a geologist, a pursuit which his knowledge of chemistry and mineralogy rendered easy to him. What agriculture he learned in Norfolk was of the greatest use to him, and he visited Flanders to learn more. He travelled from Rotterdam through Holland, Brabant, Flanders, and Picardy, and was highly delighted with the cultivation of the small holdings of those countries. Though his principal object in this excursion was to acquire information in the practice of husbandry, he appears to have paid much attention to the mineralogy of the countries through which he passed. Then he returned and took up his own farm in Berwickshire, bringing with him a Norfolk ploughman. He set to work and farmed, using every known improvement, and he has the credit of being one of those who introduced the new husbandry into a country where it has since made more rapid advances than in any other part of Great Britain. From 1754 to 1768 he resided on his farm, visiting Edinburgh occasionally. He seems to have led a tranquil country life, succeeding as a farmer; and yet there was, during all this time, a slow yet progressive growth of a science in his mind. Cautious, persevering, observant, and truly logical in his method of thought, Hutton was accumulating facts upon which to reason in geology, whilst the so-called geologists of the day were forming theories without facts. He took a tour to the north of Scotland, through Ross and Caithness, and returned by way of Aberdeen to Edinburgh, and he studied the mineralogy and geology of the districts. Returning home, he still went on farming, and at the same time he became a partner with his friend Davie in a manufactory of ammonia. By the year 1768, being forty-two years of age, Hutton had matured his plans; he let his farm at a very advantageous rent, and, untroubled about his affairs, having his three sisters as his companions, he went to Edinburgh, and entered the singularly interesting scientific society of that time. His biographer, Playfair, writes that Hutton, “employed in maturing his views and studying nature with unwearied application, now passed his time most usefully and agreeably to himself, but in silence and obscurity with respect to the world.” “Free from the interruption of professional avocations, he enjoyed the entire command of his own time, and had sufficient energy of mind to afford himself continual occupation.” A good deal of his leisure was now employed in the prosecution of chemical experiments. In one of these he made an interesting discovery which relates to the changes that go on in apparently most unchangeable rocks, and which are due to the action of percolating water on them. He noticed that in the midst of dense masses of hard, cold, volcanic rock, called basalt, crystals of great beauty are found in cavities. They can be fused under the blowpipe easily, and that is not the case with the surrounding rock. On adding hydrochloric acid to one of these zeolites, as they are called, a gelatinous substance is formed out of the crystal, and on evaporation, sea salt or chloride of sodium is found. “This was the first instance,” writes his biographer, Playfair, “of an alkali being found in a stony body.” He went to Cheshire to see the salt mines, went to Birmingham, and then set out for Wales. His desire was to trace the hard gravel of granular quartz which is found in such abundance in the soil about Birmingham and elsewhere, to its origin, and to find out whence it came and how it was distributed. He found none of the rock in Wales; but on returning he found it in places, in a body of old rocks which stand out of the country between Bromsgrove and Birmingham.

Then Hutton wrote a little book on the “Nature, Quality, and Distinction of Culm and Coal.” The result was more economical than scientific, for it led to the abolition of a duty on the small coal of Scotland. He read hard, and every book on travels which referred to physical geography was carefully studied, so that at last no man of the age was so fit to deal with the great problem he had been revolving in his mind for thirty years. All his studies of nature, all his examinations of the surface of the earth, were with a view of ascertaining the changes that have taken place on its surface, and of discovering the causes by which they have been produced. He was impressed with the belief that the former changes in the earth’s surface have been of the same kind as those now in progress; that the ancient history of the earth could only be studied by taking the example of modern changes, and that the past could be studied from the present, because there was uniformity and constancy and law in nature. The same energies and forces have always been and have acted by law in much the same manner as at the present time. With his true scientific spirit Hutton would have nothing to do with convulsions or with the origin of the globe; he did not want to guess or speculate, but to argue logically on facts which anybody could observe. He took geology out of the age of the marvellous and laid the foundations of the present aspect of the science. He was in no hurry to publish his views, possibly because his temperament was cautious, and possibly he was aware what a furious fuss there would be made about it; how he would be abused, scolded, and anathematized. There is no doubt that the lights of the age and public opinion were perfectly incompetent to judge the merits of such a theory; they were sunken in prejudices, and resisted any change of opinion. He was aware that a great outcry would be made by men whose religious opinions were his own, and whom he respected greatly. In fact, the world, just before the appearance of Hutton’s “Theory of the Earth,” was less prepared for it than ordinary opinion was for the doctrines of Charles Darwin one hundred years afterwards. The appearance of the work of this last great naturalist made, and is still making, a great stir, but that of Hutton’s work was received, as he anticipated, with incredible opposition, by the teachers of the day; and its slow acceptation by the scientific world was remarkable. No abuse could efface its effects; it was true, and the true alone lasts; it was reasonable, and it was to the glory of God.

In this book, geology was, for the first time, declared to be in no way concerned about the origin of things. It was the first in which an attempt was made to dispense entirely with all hypothetical causes, and to explain the former changes of the earth’s crust by reference exclusively to such natural agents as still exist. Hutton laboured to give fixed principles to geology, as Newton had succeeded in doing to astronomy. He wrote: “The ruins of an older world are visible in the present structure of our planet, and the strata which now compose our continents, have been once beneath the sea, and were formed out of the waste of pre-existing continents. The same forces are still destroying, by chemical decomposition or mechanical violence, even the hardest rocks, transporting the materials to the sea, where they are spread out and form strata analogous to those of more ancient date. Although loosely deposited along the bottom of the ocean, they become afterwards altered and consolidated by volcanic heat, and then turned up, fractured, and contorted.” He showed that many hard crystalline rocks, such as basalt, were of igneous origin, and that some of them had been injected in a melted state through fissures in the older strata. He proved, by examining Glen Tilt, that granite was once in a state of fusion, and had cooled. He wrote: “In the economy of the world I can find no traces of a beginning, no prospect of an end,” a declaration all the more startling when coupled with the doctrine that all changes on the globe had been brought about by the slow agency of existing causes. Sir Charles Lyell, writing on this, stated, “The imagination was first fatigued and overpowered by endeavouring to conceive the immensity of time required for the annihilation of whole continents by so insensible a process; and when the thoughts had wandered through these intermediate periods, no resting place was assigned in the remotest distance. The oldest rocks were represented to be of a derivative nature, the last of an antecedent series, and that, perhaps, of one of many pre-existing worlds.”

Most unfairly was Hutton attacked, and he was thus defended by his friend Playfair: “In the planetary motions, where geometry has carried the eye so far, both into the future and the past, we discover no mark either of the commencement or termination of the present order. It is unreasonable, indeed, to suppose that such marks should anywhere exist. The Author of nature has not given laws to the universe, which, like the constitutions of men, carry in themselves the elements of their own destruction. He has not permitted in his works any symptom of infancy or of old age, or any sign by which we may estimate either their future or their past duration. He may put an end, as He no doubt gave a beginning, to the present system at some determinate period of time; but we may rest assured that this great catastrophe will not be brought about by the laws now existing, and that it will not be indicated by anything which we perceive.”

Hutton studied meteorology, and gave to the world the first reasonable theory of the cause of rain. He described the formation of invisible vapour by evaporation, the production of visible mist and cloud, and finally rain. And he investigated the reasons of the cause of rainfalls differing in amount in the tropics and temperate zones of the earth. In 1793 serious illness attacked Hutton after he had been writing his speculations regarding matter. On his recovery he republished his work on the “Theory of the Earth,” and replied to many of the attacks upon it, and later on wrote a work which was not published in the “Elements of Agriculture.” Illness again seized him, and he died in 1797.