Hutton, James

(b. Edinburgh, Scotland, 3 June 1726; d. Edinburgh, 26 March 1797)

geology, agriculture, physical sciences, philosophy.

Hutton was the only son of William Hutton, a merchant and former city treasurer in Edinburgh, and Sarah Balfour, daughter of John Balfour, another Edinburgh merchant, whose descendants provided two professors of botany at Edinburgh University. William Hutton died in 1729 when James was three years old. His will indicates that he left the family, including Hutton’s three sisters, quite well-off, and apparently Hutton was never under any pressing need to earn a living. He attended Edinburgh High School and in 1740 entered Edinburgh University as a student of the humanities. He attended the lectures given by John Stevenson on logic and rhetoric and those of the mathematician Colin Maclaurin, which included physics, experimental philosophy, and geography as well as mathematics.

It is said that Hutton enjoyed Maclaurin’s lectures particularly, but his biographer John Playfair¹ states that it was to Stevenson that Hutton was indebted for his interest in chemistry, as a result of an experiment introduced into a lecture. Little information about chemistry was then available to Hutton, but he retained and developed his interest in the subject throughout his lifetime.

On leaving the university it was apparent that Hutton had an inclination for academic studies, but he was persuaded to follow an occupation more likely to provide a professional career. Consequently, in 1743 he was apprenticed to an Edinburgh lawyer. The routine of a lawyer’s office was not to his liking, and he was soon released from his obligations. He then decided to study medicine, the only professional course which ensured that he would learn something more about chemistry. He reentered the university in 1744, and studied medicine there until 1747, probably attending the lectures of Andrew Plummer, professor of medicine and chemistry, who had studied under Boerhaave.

Toward the end of 1747 Hutton went to Paris, where he remained nearly two years. There, according to Playfair, “he pursued with great ardour the studies of chemistry and anatomy.” Because of his interest in chemistry, he probably attended G. F. Rouelle’s well-known and popular chemistry course, which also included lectures on mineralogy and geology. Thus it was possibly in Paris that Hutton first became acquainted with geology. Sometime during 1749 Hutton moved to Leiden, where he graduated M.D. in September of that year with a thesis entitled De sanguine et circulatione microcosmi.

After leaving Leiden at the end of 1749 Hutton spent several months in London. About this time he entered into an agreement with James Davie, an Edinburgh friend, to manufacture sal ammoniac from soot, by a method they had jointly discovered before Hutton had left Edinburgh. This undertaking operated successfully for many years and no doubt added to Hutton’s income.

Hutton returned to Edinburgh in the summer of 1750. He decided against practicing medicine and chose instead to take up farming as an occupation on the small farm he had inherited from his father at Slighshouses, Berwickshire, forty miles southeast of Edinburgh. Hutton recorded that he became interested in farming some years previoulsly after reading Jethro Tull’s well-known book Horse-Hoeing Husbandry. The standard of farming in Scotland at that time was low and because Hutton investigated thoroughly any subject in which he became interested, before settling at Slighshouses he spent about a year (1752-1753) on a farm at Belton, near Yarmouth, in East Anglia, an area in which good farming practice prevailed. While there he made many journeys on foot into other parts of England to study agriculture and he acquired the habit of examining rock outcrops. It was in 1753, according to Playfair, that Hutton first began to study geology. As a student of farming he must have observed that in England soils vary markedly from place to place, and this may have stimulated an interest in the subject.

In 1754 Hutton spent some months traveling in Holland, Belgium, and northern France to improve further his knowledge of agriculture, and again he took the opportunity to add to his knowledge of geology. At the end of that year he moved to Slighshouses, where he spent the next fourteen years farming his land in a more scientific manner than had hitherto been customary in Scotland. So far as is known this period of his life was uneventful, except that he made a journey to northern Scotland in 1764 with his close friend George Clerk of Penicuik² chiefly to study geology, to which, according to Playfair, Hutton was then giving much attention. Slighshouses was an isolated farmhouse and Hutton must have lacked congenial company, although one friend, Sir John Hall of Dunglass, a man interested in both farming and science, lived in the neighborhood. The future course of Hutton’s life suggests that he may have spent much time reading scientific literature, for his interests were never confined solely to geology.

In 1767 Hutton, in association with Clerk and Hall, became a member of the committee of management of a projected canal to join the Forth and Clyde rivers. He continued to take an active part in the work of the committee for some twenty years.

About 1768, after bringing his farm into good condition, Hutton was able to let it. He then moved to Edinburgh, where he spent the rest of his life, living with his unmarried sisters. There was in Edinburgh at that time a Philosophical Society (later incorporated as the Royal Society of Edinburgh). Hutton became a member and read several papers to the society, only one of which was published. Playfair states that in Edinburgh much of Hutton’s time was occupied with experimental chemistry; but he published nothing on the subject until late in his career. A visitor to his apartment in 1772 recorded that “his study is so full of fossils and chemical apparatus that there is hardly room to sit down.”

Hutton was by temperament both sociable and hospitable and he entered fully into the intellectual and social life of the city. Joseph Black became his most intimate friend. Others of about his own age with whom he associated closely were Adam Smith, James Lind (1736–1812), Adam Ferguson, James Burnett (Lord Monboddo), John Hope, and John Walker. Through Black he became a friend of James Watt, in whose work he took much interest. About 1781 he first met Playfair,³ and later he befriended Sir James Hall, who attained distinction as a geologist and chemist.

In 1774 Hutton made another tour into England and Wales. He visited Birmingham and with Watt examined the salt mines in Cheshire. In an unpublished letter to George Clerk he reported that he had been studying both geology and agricultural practice during this tour; and he implied that he was now familiar with the geology of England, with the exception of Cornwall. He later obtained a report on the geology of Cornwall from Watt’s son, Gregory. During Hutton’s tour the elder Watt probably introduced him to some members of the Birmingham discussion group later known as the Lunar Society, for he afterward corresponded with Erasmus Darwin and Mathew Boulton.

In 1777 Hutton published in Edinburgh a small pamphlet entitled Considerations on the Nature, Quality, and Distinctions of Coal and Culm. Its purpose, commercial rather than geological, was to establish the claim that the low-grade stony coal (culm) then exported from Edinburgh for lime burning should qualify for a lower rate of duty. This pamphlet, and Hutton’s association with the Forth and Clyde canal, suggest that the practical value of his geological knowledge was already recognized.

When the Royal Society of Edinburgh was founded in 1783, Hutton became one of its most active supporters, believing that the establishment of the Society was important for the progress of science. His active interest in geology continued and from 1785 to 1788 he visited several parts of Scotland, the Isle of Man, and England to extend his knowledge. In 1788 Hutton was elected foreign member of the French Royal Society of Agriculture. It is possibly significant that the president of the society at that time was Nicholas Desmarest.

After 1788, so far as is known, Hutton made no more field excursions; and from 1791 he was subject to recurrent illness.⁴ He spent these years preparing his lesser known works on chemistry, physics, and philosophy for publication. In 1795 he published the definitive two-volume edition of his Theory of the Earth. His friends had previously urged him to publish this work, and he was finally prompted to do so to counter Richard Kirwan’s strong criticism of the theory.⁵ Finally, Hutton began the preparation of another work, the “Principles of Agriculture,” but his death prevented its publication.

The variety of subjects that Hutton studied intensively, and his general way of life, indicate that he was a man interested in knowledge for its own sake, without thought of personal advancement, and his works show an overriding intent to fit all the subjects he discussed into the framework of his deistic philosophy.

The illness that led to Hutton’s death was stated by Black to have been caused by stones in the bladder. The first attack in 1791 was cured by a severe operation, but a recurrence set in during 1794. Thereafter he was confined to his house, although he remained cheerful, mentally alert, and able to read and write between bouts of severe pain.

Hutton never married; he was survived by one unmarried sister, Isabella, and a natural son, James, probably born about 1747, when Hutton was still a student. His son, employed for many years in the General Post Office in London, married and raised a family. Hutton kept in contact with him, providing money when he was in need. After Hutton died, Isabella Hutton presented his geological specimens to Black, who, in turn, gave them to the Royal Society of Edinburgh, on conditions which should have ensured that they would be properly cataloged and preserved. A few years later they were transferred to the university museum, then curated by Robert Jameson. They were exhibited for a time, but ultimately disappeared and no trace of them has since been found.

Geology. Hutton’s most important contribution to science was his theory of the earth, first announced in 1785. Hutton had then been actively interested in geology for fully thirty years. It is known that he had completed the theory in outline some years earlier, and according to Black, writing in 1787,⁶ Hutton had formed its principal parts more than twenty years before. In essence the theory was simple, yet it was of such fundamental importance that Hutton has been called the founder of modern geology. Much has been written about the scientific and intellectual background in eighteenth-century Europe at the time Hutton formed his theory, but its novelty can only be appreciated when related to the existing state of geological knowledge.

Interest in various branches of the earth sciences was then widespread, but recognition of geology as an individual science had scarcely begun. The mining of economic minerals was one of the oldest industries, but the development of scientific mineralogy was retarded by the undeveloped state of chemistry and crystallography. Nevertheless, through mining and quarrying operations, a knowledge of stratigraphy must have been acquired locally, but it remained rudimentary because of the almost universal belief that the fossiliferous sediments had been deposited by, or during the retreat of, the Noachian flood. While fossils themselves had long aroused interest (it was recognized that some forms could not be matched by known living species) their value as chronological and stratigraphic indexes had not yet been recognized except, perhaps, over very limited local stratigraphic ranges.

Crystalline rocks such as granite and gneiss, usually found in the core of mountain ranges, were regarded as primeval in age, and the sediments, often fossiliferous, on the flanks of the mountains and in low ground were assumed to be flood deposits. This classification carried no implication that any rocks were older than the five or six thousand years allowed for in biblical chronology. By about the middle of the eighteenth century, however, one or two authors had suggested that geological time might be longer than this chronology allowed. The effects of erosion, long recognized, formed a subject for debate over whether denudation would ultimately render the earth uninhabitable, or whether it would be compensated by the elevation of new lands on which life would continue.

There existed one major gap in geological knowledge. It was unsuspected that rocks of the type now classed as igneous formed a major and widely distributed rock group, wholly distinct in origin from the sediments. The extrusion of lava from active volcanoes was looked on as a local and superficial phenomenon. After about 1740, Italian and French naturalists recognized the existence, locally, of volcanic cones and lava flows in areas where there was no record of volcanic activity in historic times; but many years passed before it was realized that volcanic activity had been worldwide, not only in historic times but in past geologic ages. The igneous origin of many rocks interbedded in, or otherwise closely associated with, the sediments was still unrecognized.

Broadly speaking, the position was that many geological observations had been made and recorded in the literature; but previous attempts to synthesize these observations into a general “theory of the earth” were unscientific and had not proved acceptable. The issue had been confused and progress retarded by a literal belief in the biblical account of creation and the universal flood.

The Theory of the Earth . Hutton’s theory, or “System of the Earth,” as he called it originally, was first made public at two meetings of the Royal Society of Edinburgh, early in 1785. The society published it in full in 1788, but offprints of this paper were in circulation in 1787, and possibly in 1786. The theory first appeared in print in condensed form, in a thirty-page pamphlet entitled Abstract of a Dissertation... Concerning the System of the Earth, Its Duration, and Stability, which Hutton circulated privately in 1785. The interest of this pamphlet is that it states all the conclusions which were essential to the theory as a whole. It emphasizes that even at this early date Hutton’s thinking was far ahead of that of his contemporaries. For this reason, and because it is more easily comprehended than the full version, it is summarized here.

Hutton’s approach in the Abstract is logical, but his thought is not translated into clear and incisive prose. As with almost all that he wrote (other than private letters), his style is prolix and abstruse, so that the text must be read with care to appreciate its full significance.

Hutton describes briefly his purpose in carrying out the inquiry, the methods he employed in reaching his conclusions, and the conclusions themselves. His purpose was to ascertain (a) the length of time the earth had existed as a “habitable world”; (b) the changes it had undergone in the past; and (c) whether any end to the present state of affairs could be foreseen. He stated that the facts of the history of the earth were to be found in “natural history,” not in human records, and he ignored the biblical account of creation as a source of scientific information (a view he expressed explicitly later on). The method he employed in carrying out his inquiry had been a careful examination of the rocks of the earth’s crust, and a study of the natural processes that operated on the earth’s surface, or might be supposed, from his examination of the rocks, to have operated in the past. In this way, “from principles of natural philosophy,” he attempted to arrive at some knowledge of the order and system in the economy of the globe, and to form a rational opinion as to the course of nature and the possible course of natural events in the future.

Hutton concluded that rocks in general (clearly he referred here to the sedimentary rocks) are composed of the products of the sea (fossils) and of other materials similar to those found on the seashore (the products of erosion). Hence they could not have formed part of the original crust of the earth, but were formed by a “second cause” and had originally been deposited at the bottom of the ocean. This reasoning, he stated, implies that while the present land was forming there must have existed a former land on which organic life existed, that this former land had been subjected to processes of erosion similar to those operating today, and that the sea was then inhabited by marine animals. He then concluded that because the greater part of the present land had been produced in this way, two further processes had been necessary to convert it into a permanent body resistant to the operations of water: the consolidation of the loose incoherent matter at the sea bottom, and the elevation of the consolidated matter to the position it now occupies.

Hutton then considered two possible methods of consolidation. The first, deposition from solution, he rejected because the materials of which ordinary sediments are composed are, with few exceptions, insoluble in water. He adopted the alternative, fusion of the sediments by the great heat which he believed to exist beneath the lower regions of the earth’s Crust. Heat, he claimed, was capable of fusing all the substances found in different types of sediment.

He also concluded that the extreme heat that fused the sediments must be capable of “Producing an expansive force, sufficient for elevating the land from the bottom of the ocean to the place it now occupies.” He supported this conclusion by stating that the strata formerly deposited in regular succession at the bottom of the ocean are now often found broken, folded, and contorted, a condition to be expected as a result of the violently expansive action of subterraneous heat.

Hutton then discussed the direct evidence of the action of heat, which he had found in the rocks themselves. He mentioned mineral veins containing matter foreign to the strata they traverse, the widespread occurrence of volcanoes, and the occurrence of what he called “subterraneous lavas.” (The examples quoted here, and in the fuller version of the theory, indicate clearly that he was referring to what are now known as igneous intrusions.)

Hutton next claimed that his theory could be extended to all parts of the world, a generalization that was by then justified because similar rocks occur in other countries. He also claimed that the theory, based on rational deductions from observed facts, was not “visionary.”

Finally, Hutton discussed one of the principal objects of his inquiry, the length of time the earth had existed as a habitable world, that is, in effect, the question of geological time. He rejected as humanly impracticable the possibility of estimating geological time by measuring the rate at which erosion is wearing down the land. Hence he concluded

... That it had required an indefinite space of time to have produced the land which now appears;... That an equal space had been employed upon the construction of that former land from whence the materials of the present came;... That there is presently laying at the bottom of the ocean foundation of a future land, which is to appear after an indefinite space of time..... so that, with respect to human observation, this world has neither a beginning nor an end [pp. 27-28].

Hutton was not prepared to be more definite than the facts allowed.

It was also in the Abstract that Hutton disclosed for the first time his philosophic belief that there exists in nature evidence of wisdom and design. He believed that the natural processes operating on an within the earth’s crust had been so contrived as to provide for the indefinite continuance of the earth as a habitable world, providing means for the continuing existence of living beings, and that his theory provided support for this conclusion. The final paragraph of the Abstract includes the following statement: “Thus, either in supposing Nature wise and good, an argument is formed in confirmation of the theory, or, in supposing the theory to be just, an argument may be established for wisdom and benevolence to be perceived in nature.” Hutton’s theory ran counter to the belief then widely held that the present world was created by a divine being, fully populated by animal and plant life, at a time that could be measured by human records.

Hutton makes few references in the Abstract to the evidence on which he bases his theory. This is discussed in detail in his 1788 paper. Here, in discussing geological time, the conclusion he draws from fossils is of particular interest. He states:

Time...is to nature endless and as nothing.... The Mosaic history places this beginning of man at no great distance; and there has not been found, in natural history, any document by which a high antiquity might be attributed to the human race. But this is not the case with regard to the inferior species of animals... We find in natural history monuments [that is, fossils] which prove that those animals had long existed; and we thus procure a measure for the computation of a period of time extremely remote, though far from being precisely ascertained [pp. 215, 217].

From 1785 onward Hutton continued to collect new information to support his theory, which he published later in a two-volume work, Theory of the Earth: With proofs and Illustrations; in Four Parts(1795). In this edition the 1788 theory is restated with no essential change in the first chapter of volume I. The remainder of the two volumes deals principally with the supporting proofs and illustrations. Only two of the four parts promised on the title page were published in 1795. Hutton left an unfinished manuscript containing six chapters totaling 267 pages, evidently intended for inclusion in an additional volume of the Theory. These chapters, published as volume III in 1899, are of considerable interest, for they contain accounts of several of his later geological journeys. A study of the three volumes reveals the remarkable extent of Hutton’s geological knowledge, the thoroughness of his investigations, and the acuteness of his observations.

The methods Hutton had employed in forming his theory were essentially the same as those employed by modern field geologists. He examined many different types of rocks, paying attention to their structural relations one to another; and he considered in detail the mineralogical and chemical composition of individual rocks. He also studied intensively the physical processes now operating on the earth’s surface. In addition he examined British, European, and American literature to find support for his conclusions.

The method he employed in formulating his theory was, as he claimed, based on the principles of natural philosophy. Some of his conclusions can be described as speculative, and others were based on misinterpreted evidence, but these elements in the theory do not destroy its validity as a whole. It could be argued that Hutton’s theory incorporated ideas that he had gained from other authors. This question is difficult to answer, for although he had read extensively, he seldom if ever quotes the work of another author in a manner that suggests he had made use of his ideas. More often, references are made either to correct a particular author, or to confirm Hutton’s own conclusions. His originality lies in the use he made of facts and ideas, not in their sources.

The most important advance in geological science embodied in Hutton’s theory was his demonstration that the process of sedimentation is cyclical in operation, a principle now accepts as axiomatic. Hutton’s cyale involved the gradual degradation of the land surface by erosion; the transport of eroded matter to the sea, there to be deposited as sediments; and the consolidation of the sediments on the sea bottom, followed by their elevation to form new land surfaces, which in turn were subject to erosion. Hutton showed that this cyclic process must have been repeated an indeterminate number of times in the past, and because he could find no evidence to suggest that it might cease, he assumed that it would continue indefinitely.

In constructing his theory Hutton had used as a working hypotheses the assumption, based on his own observations, that the geological evidence provided by surface rocks provided both a key to the past and an indication of the probable future course of events. His theory formulated for the first time the general principle that some fifty years later came to be known as uniformitarianism.

In the fields of physical geology and gemorphology Hutton’s views were strikingly modern. His knowledge of the processes of erosion and the agents that activate these processes, particularly river action, was through. His imaginative reasoning led to one remarkable conclusion about the possible action of glaciers in Switzerland. He had read in H. B. de Saussure’s Voyages dans les Alpes (Neuchatel, 1779) a description of scattered boulders of granite, often of immense size, which rested on limestone in the Saleve area, and had obviously been transported there from a distant source. De Saussure believed that their presence could not be accounted for by river action, and he suggested that they had been brought there by a vast debacle or general flood. Although he had not visited Switzerland, Hutton proposed a solution much nearer the truth. He suggested that in the past, when the height of the Alps had been very much greater. “immense valleys of ice sliding down in all directions towards the lower country, and carrying large blocks of granite to a great distance” (Theory, II [1795], 218), had transported these erratic blocks; and that in the course of time the upper parts of the mountains that had carried these glaciers had been removed by erosion. The true explanation, that the distribution of erratics of this sort had been effected by great ice sheets covening much of Europe, was not put forward until some forty years later.

Hutton also made contributions, second only in importance to his main theory, in the field of igneous geology. He was much impressed by the worldwide distribution of volcanic activity, and by the new discoveries that in some areas there occurred lavas that must have been erupted in prehistoric times. He made a detailed study of the numerous outcrops of igneous rocks in or near Edinburgh (some almost on his own doorstep), and of others in various parts of Scotland. He distinguished two types, lavas and intrusions, including among the latter both flat sheets and dyes, and he established for the first time the existence of a new class of rocks, the intrusive igneous rocks. He concluded that all igneous rocks originated in what he called the “mineral region,” a subcrustal zone of undefined depth in which heat of sufficient intensity to melt rocks prevailed.

Hutton also established the igneous origin of granite, a rock hitherto classed as primeval and believed by geologists of the Wernerian school to have been deposited from water. His study of granite affords an instructive example of Hutton’s acute powers of observation and reasoning and the fact that, in general, he did not reach conclusions without sound evidence to support them.

In his 1788 paper he mentioned that some of the rocks of the earth’s crust are not stratified, in particular granite. He reserved judgment on the question of the origin of granite but claimed that if one species of granite could be shown to have existed in a state of fusion, then this conclusion could be extended to other varieties of the same rock. He described a particular, and quite abnormal, type of granite from Portsoy, in northeast Scotland, a specimen of which had been sent to him. He had not seen the outcrop but had been informed that it graded into granite of normal type.

This specimen (see Figure 1), illustrated in his 1788 paper, is clearly an example of the variety known as graphic granite, owing to a superficial resemblance to oriental writing evident when the rock is broken in a particular direction, perpendicular to the long axis of the contained quartz crystals which are embedded in a groundmass of feldspar. The Quartz crystals then appear skeletal in form, with reentrant angles. Hutton concluded “it is not possible to conceive any other way in which these two substances, quartz and feld-spar, could thus be concreted, except by congelation [cooling] from a fluid state, in which they had been mixed” (“Theory” [1788], p. 256). That is to say the rock had cooled from a fused melt. This was a sound conclusion, for there is nothing in the appearance of the rock to suggest a sedimentary origin.

In a later paper, read to the Royal Society of Edinburgh in 1790, Hutton indicated that he had previously reserved judgment on the granite question as a whole, because he had not then decided whether granite.

... was to be considered as a body which had been originally stratified by the collection of different [that is, sedimentary] materials, and afterwards consolidated by the fusion of these materials; or whether it were not rather a body transfused from the subterraneous regions, and made to break and invade the strata in the manner of our whinstone or trapp ["Observations on Granite,” in Transactions of the Royal Society of Edinburgh, 3 (1794), 77–78].

Hutton knew of the existence of foliated granite gneisses in Scotland, and he had read that such rocks were known to de Saussure in Switzerland, who had distinguished them from massive unfoliated granite. Hutton therefore suspended judgment until he had examined the margin of an outcrop of massive granite. This he did in the autumn of 1785 when visiting the duke of Atholl’s estate at Glen Tilt, Perthshire. There Hutton found “the most perfect evidence, that granite had been made to break the Alpine strata, and invade that country in a fluid state. This corresponded perfectly with the conclusion which I had drawn from the singular specimen of the Portsoy granite” (ibid., 79–80). Hutton made journeys into other parts of Scotland where he obtained further confirmation of his conclusion. The school of geologists who accepted Hutton’s ideas about the origin of igneous rocks came to be known as “plutonist,” a name first used by Kirwan.

While the thoroughness of Hutton’s investigations and the ingenuity of his arguments are evident, some of his deductions and conclusions were unjustified. This was especially true in his discussions of the causes that he suggested were responsible for the consolidation and elevation of the strata. Here he was breaking new ground and attempting to solve problems that for the most part were insoluble at that time. He must have realized that is his theory was to be accepted, these problems could not be ignored. The solutions he reached were unduly influenced by the powers he attributed to the hot “mineral region” that he believed existed below both the continents and the oceans, powers for which he could produce little convincing evidence, although a source of heat was certainly present.

In discussing consolidation, although he did not consider seriously the possibility that compaction might have resulted from the pressure exerted by a thick mass of sediments, he did suggest that pressure could have driven the water out of porous rocks. Some of the rocks with which he was familiar, particularly the dynamically metamorphosed sediments in the Scottish Highlands and some unmetamorphosed limestones, were crystalline. This knowledge appears to have influenced him in reaching the conclusion that consolidation had been effected by heat. He claimed that many, although not all, the sediments had actually been fused. A difficulty inherent in this argument was that heat of the intensity he envisaged would have decomposed limestones. He dealt with this problem in the following statement:

The essential difference, however, between the natural heat of the mineral regions, and that which we excite upon the surface of the earth, consists in this; that nature applies heat under circumstances which we are not able to imitate, that is, under such compression as shall prevent the decomposition of the constituent substances, by the separation of the more volatile from the more fixed parts [Theory, I (1795), 140].

Sir James Hall was later to prove experimentally that this assumption was justified.

The problem raised by Hutton’s demonstration that consolidated strata had been elevated to form dry land was a formidable one. He might perhaps have evaded the issue, as others had done, by suggesting that elevation had resulted from the operation of some cataclysmic action comparable in kind to that which brought about earthquakes. Had he done so, his theory might have received less criticism, but that was not Hutton’s way. He wished to get to the root of the matter. He was clearly impressed by the immense force exerted by volcanic activity, in breaking through great thickness of consolidated strata, followed by the eruption of lava with explosive violence; and, as he indicated in the Abstract, he supposed that the shattering and distortion of strata that once existed as undisturbed horizontal beds must have resulted from the action of the same force. He was also familiar with all the properties of heat known at that time, including its expansive effects on solids, liquids, and gases. He inferred, correctly, that there must exist in his “mineral region” a potential source of immense power (now it would be termed energy), and he assumed that it was heat that brought this power into action. He therefore concluded “that the land on which we now dwell has been elevated from a lower situation by the same agent employed in consolidating the strata... this agent is matter actuated by extreme heat, and expanded with amazing force” (“Theory” [1788], p. 266). He made no attempt to explain matters in more detail, but he qualified his conclusion by adding, “The raising up of a continent of land from the bottom of the sea is an idea that is too great to be conceived easily in all parts of its operation, many of which are perhaps unknown to us” (ibid., p. 295). That Hutton failed to solve this problem, one that continues to engage the attention of geologists, is not surprising, but at least he attempted to solve it scientifically.

Reception of the Theory . It has often been stated that Hutton’s theory was little understood before the publication in 1802 of Playfair’s Illustrations of the Huttonian Theory of the Earth. This may be true, and certainly Lyell seems to have derived his knowledge of Hutton’s views principally from this source.⁷ Neverthless the theory had been widely read before then, for it had already received critical notices in both British and foreign publications; translations of the Abstract and 1788 “Theory” had appeared in Germany⁸ and France; and the theory had received some notice at least as early as 1805 in the United States. Undoubtedly Hutton’s views became quite widely known in the early years of the nineteenth century. Yet in spite of the growing interest in geology, and the rapid accumulation of factual observations, it was not until after 1830 that his theories began to gain general acceptance, largely because of Playfair’s Illustrations and the publication of Lyell’s Principles of Geology (London, 1830-1833). Lyell accepted most, although not all, of Huton’s views, and expounded them fully in his book; but he and his followers did not accept Hutton’s conclusions on the importance of the erosional action of rivers. Some thirty years passed before geologists in both Great Britain and the United States realized that Hutton had been right.

The delay in the recognition of Hutton’s work can be attributed to a variety of causes acting collectively: the natural conservatism of many geologists; reluctance to abandon belief in the biblical account of creation; the widespread influence of geologists of the Wernerian school; and the rise of catastrophism. By 1830, however, geologists, although still conservative in outlook, were much better equipped to assess the value of the Huttonian theory.

Agriculture and Evolution . Hutton must have retained an interest in agriculture long after he ceased farming, for shortly before he died he was engaged in preparing for publication a treatise entitled “Principles of Agriculture.” This has survived as a manuscript of 1045 pages. Hutton stated in the preface that his objectives in writing this treatise were to assist the farming community to judge whether they were farming on sound scientific and economic principles; to promote the general good of the country; and for his own “pleasure in what has been in a manner the study of my life.”

The treatise, based partly on Hutton’s own experience and partly on the practice of the most successful husbandmen of his time, covers all branches of farming and animal husbandry, including implements and economics, and where appropriate, Hutton applied his scientific knowledge.

The most noteworthy part of the treatise appears in a section dealing with animal husbandry. Here Hutton outlined a theory of evolution. The question he raised was “how those varieties, which we find in every species, are procured; whether by simple propagation from original models, which had been created with the species, or whether from certain laws of variation, in the process of propagation of each species by the influence of physical causes” (p. 735). Using the dog as his example of a “species,” Hutton found it “almost inconceivable” that the numerous different types of dog, “so wisely adapted to various different purposes,... should have arisen from the influence of external causes alone” (p. 736), unless “some intended principle in the original constitution of the animal” had operated. He then argued that without this factor, if several varieties or species of dog had existed originally, promiscuous interbreeding would have resulted ultimately in the production of a variety of dog with indefinite characteristics, a “compound species” or mongrel, and all the original varieties would probably have been lost; and we should never have seen “that beautiful illustration of design” exemplified in the different types of dog.

Hutton therefore suggested that originally the “species” had existed in only one form, and there was inherent in the constitution of the animal “a general law or rule of seminal variation” which would bring about constant changes in the animal, to a greater or lesser extent, “by the influence of external causes.” Thus we should find varieties in the species “propagating for a long course of time under the influence of different circumstances, or in different situations; and we should in this see a beautiful contrivance for preserving the perfection of the animal form, in the variety of the species... . To see this beautiful system of animal life (which is also applicable to vegetables)” (pp. 738-739), Hutton wrote, we must consider that

... in the indefinite variation of the breed the form best adapted to the exercise of those instinctive arts, by which the species is to live, will be most certainly continued in the propagation of this animal, and will be always tending more and more to perfect itself by the natural variation which is continually taking place. Thus, for example, where dogs are to live by the swiftness of their feet and the sharpness of their sight, the form best adapted to that end will be the most certain of remaining, while the forms that are least adapted to this manner of the chace will be the first to perish [p. 739].

Hutton’s conclusion that there is some inherent mechanism in “species,” such as seminal variation, which could lead to the establishment of animal varieties may possibly have been suggested to him by his knowledge of the animal breeding experiments carried out by the eighteenth-century agriculturist Robert Bakewell, to whom he refers elsewhere in this section of the “Principles.”

Physical Sciences. Hutton’s interest in the physical sciences, particularly chemistry, physics, and meteorology, extended over many years, during which he kept himself informed of their progress. Toward the end of his life he published a three-part book entitled Dissertations on... Natural Philosophy, which is of considerable interest to the historian of science. The conclusions he reached in this work were often original and sometimes supported by experiments he had carried out himself. The principal subjects discussed are meteorology, phlogiston, and the theory of matter.

Part 1 contains four dissertations on meteorology, of which three, dealing with Hutton’s theory of rain and his answer to DeLuc’s critcism theory of the theory, had been previously published by the Royal Society of Edinburgh (1788, 1790). The fourth contains a discussion on winds. Hutton attributed the origin of rain to a mixture of air currents of different temperatures, saturated or nearly saturated with moisture. His theory attracted attention for some years, including a favorable comment from John Dalton as late as 1819, although J. D. Leslie had already shown it to fail on qualitative grounds in 1813.

Part 2 is entitled a “Chymical Dissertation Concerning Phlogiston, or the Principle of Fire,” a subject evidently of particular interest to Hutton. It had been the topic of a paper he read to the Royal Society of Edinburgh in 1788, following an address by Sir James Hall on Lavoisier’s new chemical ideas, to which Hall had been converted after visiting Lavoisier in Paris. These papers and the accompanying discussion occupied five meetings, but they were not published.

Hutton accepted the major advances made by Lavoisier, but took the view that the concept of phlogiston had been too hastily rejected. He did not accept Lavoisier’s concept of calorique; in fact he strongly opposed it. His view was that heat, light, and electricity were all modifications of what he called “solar substance.” Hutton also considered phlogiston to be some form of the solar substance, a principle of inflammability, without gravity, which could be transferred from one substance to another. He claimed that phlogiston was actually formed by vegetative matter and decomposed during the processes of breathing and burning.

Thomas Thomson, when discussing Hutton’s views on phlogiston, described him as “a man of undoubted genius,” but stated also that his views were set out in a “manner so peculiar, that it is scarecely more difficult to procure the secrets of science from Nature herself, than to dig them from the writing of this philospher,” ⁹ Fortunately Hutton’s conception of the nature and function of phlogistion has been discussed by J. A. Partington and D. McKie in sufficient detail to meet the needs of most readers.

Part 3 of the Dissertations on... Natural Philososphy, entitled “Physical Dissertations on the Powers of Matter, and Appearances of Bodies,” constitutes more than half the book and contains Hutton’s theory of matter. Briefly summarized, this theory suggests that to describe a body as made of small particles does not explain its nature, because if we suppose these particles to possess magnitude, we do no more than say large bodies are made of smaller bodies. Therefore the elements of a body must be something unextended. To these elements he gave the name “matter,” reserving the name “body” to combinations of matter subject to powers of forces acting in various directions. He uses this conception to explain the various physical properties of bodies. Playfair emphasized the close affinity of Hutton’s theory to that of Bošcović, but he states specifically there was no reason to suppose Hutton had derived his conclusions from the latter. According to Playfair, Bošcović’s theory was hardly known in Scotland before 1770, whereas the earliest sketches of Hutton’s theory were of much earlier date.¹⁰

Hutton continued his discussion of phlogiston in his last book, Philosophy of Light, Heat, and Fire (1794). Here he also raised the question whether there might be a species of light capable of producing heat in bodies without affecting the sense of sight. This idea, he stated, had been suggested to him by his own experience, he hoped to test it accurately when suitable apparatus could be constructed. He proposed the use of either a prism or colored glass to produce both red and blue light, but the only experiment he actually carried out was a crude one. He adjusted the position of two source of light, a coal fire for red light, and a flame for “compound” or white light, so, that each sources just permitted him to read, and he found that the amount of heat given off by the fire was much greater than that from the flame. He suggested, by analogy, that invisible light should exist, which would form a source of heat greater than that produced by the visible range of the spectrum: A few years later, William Herschel investigated the subject move thoroughly, confirming Hutton’s suggestion.

Hutton’s last contribution to chemistry was a paper on the “Sulphurating of Metals,” read to the Royal Society of Edinburgh by a friend on 9 May 1796. The subject is discussed in terms of Hutton’s ideas about light, heat, and phlogiston, and a correction is made of a conclusion he had drawn Light, Heat and Fire.

Philosophy . In 1794 Hutton published a threevolume treatise on metaphysics and moral philosophy entitled An Investigation of the Principles of Knowledge. This work followed on or arose out of his studies of the physical sciences. It received little notice when it first appeared, but Playfair discussed it in some detail and suggested that if the work were abridged and the obscurities removed it would deserve more attention. It has received little if any notice since playfair’s time. In the Principles of Knowledge Hutton acknowledged the existence of a God whom he defined as “the superintending mind... a Being with perfect knowledge and absolute wisdom.” He considered nature as subordinate to God, and that the two terms were not synonymous, for God is infinite and unchangeable, but nature limited and changing. While he included the animal, vegetable, and mineral systems as part of nature’s general design, the term “nature” properly meant the whole of that action from which, in necessarily inferring design, we learn the existence of a superintending being.

Although occasionally accused of impiety in his lifetime, Hutton was not an atheist, and may be described as a deist. In almost all that he wrote, not only on geology but on agriculture and physical subjects as well, he introduced his belief that in nature there is abundant evidence of benevolent wisdom and design. To Hutton the earth as a whole was “a machine constructed upon chemical as well as mechanical principles, by which its different parts are all adapted, in form, quality, and in quantity, to a certain end... an end from which we may perceive wisdom in contemplating the means employed” (“Theory” [1788], p.216). The earth, in Hutton’s view, was evidently made for man, will be led “to acknowledge an order, not unworthy of Divine wisdom, in a subject which, in another view, has appeared as the work of chance, or absolute disorder and confusion” (ibid., P. 210).

Hutton’s attitude toward the Christian religion was recorded in a brief (Unpublished) manuscript entitled ’Memorial Justifying the Present Theory of the Earth Form the Suspicion of Impiety,” which was evidently written sometime between 1788 and 1795, in answer to criticisms of his theory. In it he made no attempt to compromise with the Church, as Buffon had done. His view was that the ancient Jewish writings on which the Christian religion was founded can be accepted only insofar as they record the history of man upon earth. He denied the literal truth of the Mosaic account of creation, whose only significance, he stated, was its record that God had made all things in a certain order; and he thought it absurd to suppose that the term “day” used in that account could mean anything other than an indefinite period of time.

Hutton maintained that it was not the duty of religion to provide a history of the natural operations that had taken place on the earth in the past; but that this was the function of man, using his intellect and applying the methods of natural philosophy. He regarded the objectives of revealed religion and natural philosophy as essentially different, and saw no reason why one should interfere with the other, provided their different purposes were kept separate.

NOTES

1. This account of Hutton’s life is based almost entirely on John Playfair, “Biographical Account."

2. Hutton was friendly with several members of a prominent scottish family, the Clerks of Penicuik. His particular friend was George, second son of Sir John Clerk who had been vice-president of the Philosophical Society of Edinburgh. George Clerk was interested in mineralogy and accompanied Hutton on several of his geological excursions. On marriage to a Miss Maxwell he assumed the name of Clerk-Maxwell, and the physicist Clerk-Maxwell is his descendant. Other members of the Clerk family accompanied Hutton on later hours.

3. See Playfair, op. cit., p. 74 n.

4. Playfair gives the date incorrectly as 1793.

5. See Kirwan, “Examination of the Supposed Igneous Origin of Stony Substances,” in Transactions of the Royal Irish Academy, 5 (1793), 51-81.

6. In a letter to Princess Dashkow, then director of the Imperial Academy of Sciences, St. Petersburg, in which Black summarizes Hutton’s theory; see W. Ramsay, Life and Letters of Joseph Black, M.D. (London, 1918), 117–125.

7. See Life, Letters and Journals of Sir Charles Lyell, II (London, 1881), 47–49.

8. Werner MSS at Freiberg, IX, has an abstract of the 1788 “Theory.”

9. See “Chemistry, (i)” in Supplement to the 3rd ed. Encyclopaedia Britannica (Edinburgh, 1801), I, 287.

10. See Playfair, op cit., p. 78 n.; see also R. Olson, “The Reception of Boscovich’s Ideas in Scotland,” in Isis, 60 (1969), 91-103.

BIBLIOGRAPHY

I. Original Works. Hutton’s published works are the following: Dissertatio physico-medica inauguralis de sanguine et circulatione microcosmi (Leiden, 1749); Considerations on the Nature, Quality, and Distinctions of Coal and Culm ... in a Letter From Doctor James Hutton ... to a Friend (Edinburgh, 1777); Abstract of a Dissertation Read in the Royal Society of Edinburgh, Upon the Seventh of March, and Fourth of April, M, DCC, LXXXV, Concerning the System of the Earth, Its Duration, and Stability (probably Edinburgh, 1785), repr. in Proceedings of the Royal Society of Edinburgh, 63B (1950), 380-382, and facs. repr. in G. W. White, ed., Contributions to the History of Geology, V (Darien, Conn., 1970), 1-30; Dissertations on Different Subjects in Natural Philosophy (Edinburgh, 1792); An Investigation of the Principles of Knowledge, and of the Progress of Reason, From Sense to Science and Philosophy, 3 vols. (Edinburgh, 1794); A Dissertation Upon the Philosophy of Light, Heat, and Fire (Edinburgh, 1794); and Theory of the Earth: With Proofs and Illustrations, vols. I–II (Edinburgh, 1795), facs. repr. (New York, 1959); vol. III (chs. 4-9), Sir Archibald Geikie, ed. (London, 1899), with indexes to all three vols.

Hutton’s papers are “The Theory of Rain,” in Transactions of the Royal Society of Edinburgh, 1 (1788), 42-86; “Theory of the Earth; or an Investigation of the Laws Observable in the Composition, Dissolution, and Restoration of Land Upon the Globe,” ibid., 209-304, facs. repr. in Contributions to the History of Geology, v (1970), 31-131; “Of Certain Natural Appearances of the Ground on the Hill of Arthur’s Seat,” in Transactions of the Royal Society of Edinburgh, 2 (1790), 3-11 (read to the Philosophical Society of Edinburgh, 1778); “Answers to the Objections of M. de Luc With Regard to the Theory of Rain,” ibid., 39-58; “Observations on Granite,” ibid., 3 (1794), 77-85, facs. repr. in Contributions to the History of Geology, V (1970), 133-139; “Of the Flexibility of the Brazilian Stone,” in Transactions of the Royal Society of Edinburgh, 3 (1794), 86-94; and “An Examination of a New Phenomenon Which Occurs in the Sulphurating of Metals, With an Attempt to Explain That Phenomenon,” ibid., 4 (1798), pt. I, History of the Society, 27-[36] (misnumbered 28).

For foreign publications of Hutton’s works, see “Theory of the Earth” (1788), noticed in Magazin für das Neueste aus der Physik und Naturgeschichte, 6 , pt. 4 (1790), 17-27, and translated in full in Sammlungen zur Physik und Naturgeschichte, 4 (1792), 622-725. A French trans. of the Abstract appeared in “Extrait d’une Dissertation sur le Systéme et Durée de la Terre... traduite de l’Anglois, par Iberti... suivi par les Observations du Traducteur,” in Observations sur la Physique, 43 (1793), 3-12. N. Desmarest, Encyclopédie méthodique. Géographie physique, I (Paris, 1794), 732-782, contains extensive extracts from the Abstract, the “Theory of the Earth,” and the “Theory of Rain,” with commentary by Desmarest.

Hutton’s extant MSS are “Principles of Agriculture” (2 quarto vols. totaling 1045 pp.), in the library of the Royal Society of Edinburgh; and the five-page “Memorial Justigying the Present Theory of the Earth From the Suspicion of Impiety,” in the Fitzwilliam Museum, Cambridge, England.

Very few letters either written by or addressed to Hutton have survived. His letters to John Strange, the geologist and diplomat, in 1770 or 1771 have been published by V. A. Eyles and J. M. Eyles as “Some Geological Correspondence of James Hutton,” in Annals of Science, 7 (1951), 316-339.

II. Secondary Literature. The only complete account of Hutton’s life is John Playfair, “Biographical Account of the Late Dr James Hutton, F.R.S. Edin.,” in Transactions of the Royal Society of Edinburgh, 5 (1803), 39-99, facs. repr. in Contributions to the History of Geology, V (1970), 141-203, repr. in The Works of John Playfair, IV (Edinburgh, 1822), 33-118. Playfair discusses critically Hutton’s published works. A few additional details about Hutton’s activities as a farmer are included in “Principles of Agriculture.”

W. Ramsay, Life and Letters of Joseph Black, M.D. (London, 1918); and Partners in Science: Letters of James Watt and Joseph Black, E. Robinson and D. McKie, eds. (London, 1970), contain interesting references to Hutton; especially to his illness and to his natural son. Other unpublished letters of Black in the library of Edinburgh University are also worth consulting. For brief references to Hutton in the published diaries and letters of contemporaries, see V. A. Eyles, “Introduction,” in Contributions to the History of Geology, V (1970), xi–xxiii.

Playfair’s Illustrations of the Huttonian Theory of the Earth (Edinburgh, 1802), repr. in The Works of John Playfair, I (Edinburgh, 1822), 1-514, facs. repr. of 1802 ed. (Urbana, 1956), with intro. by G. W. White, is widely used as a source of Hutton’s views, but does not always present them with complete accuracy. Its publication stimulated John Murray of Edinburgh, lecturer in chemistry and supporter of Wernerian geology, to publish anonymously A Comparative View of the Huttonian and Neptunian Systems of Geology (Edinburgh, 1802). The Illustrations and Comparative View, translated into French and annotated by the translator, C. A. Basset, were published in one volume, Explication de Playfair sur la Théorie par Hutton, et examen comparatif des systémes géologiques... par M. Murray (Paris, 1815).

W. H. Fitton, “A Review of Mr Lyell’s Elements of Geology’; With Observations on the Progress of the Hutonian Theory of the Earth,” in Edinburgh Review, 69 (1839), 406-466, includes a detailed discussion of ht evalue of Hutton’s theory in relation to contemporary geogical knowledge. Fitton shows that some prominent geologists of the period, particularly in France, were either unaware of Hutton’s work, or, if familiar with it, failed to acknowledge Hutton’s priority when putting forward their own conclusions.

The following modern commentaries on various aspects of Hutton’s work, principally his geology, may be consulted: “James Hutton 1726–1797, Commemoration of the 150th Anniversary of his Death,” in Proceedings of the Royal Society of Edinburgh63B (1950), 351-402, contains five articles on Hutton’s life and work: M. Macgregor, “Life and Times of James Hutton"; E. B. Bailey, “James Hutton, Founder of Modern Geology"; G. W. Tyrrell, “Hutton on Arran"; V. A. Eyles, “Note on the Original Publications of Hutton’s Theory of the Earth and the Subsequent Forms in Which it was Issued"; and S. I. Tomkeieff, “James Hutton and the Philosophy of Geology,” repr. from Trasactions of the Edinburgh Geological Society, 14 (1948), 253-276. Tomkeieff notes that G. H. Toulmin, in The Antiquity and Duration of the World (London, 1780), expressed views in some respects similar to those in Hutton’s Theory of the Earth. References to Toulmin and Hutton were also made by D. B. McIntyre, “James Hutton and the Philosophy of Geology,” in C. C. Albritton, ed., The Fabric of Geology (Reading, Mass., 1963), 1-11; and G. L. Davies, “George Hoggart Toulmin and the Huttonian Theory of the Earth,” in Bulletin of the Geological Society of America, 78 (1967), 121-124.

A useful source book and guide to Hutton’s geological thought is E. B. Bailey, James Hutton—the Founder of Modern Geology (Amsterdam-London-New York, 1967), which contains a summary of each chapter of Theory of the Earth, a well-informed commentary on Hutton’s ideas, and a less detailed discussion of his other works, particularly “Principles of Agriculture.”

R. H. Dott, Jr., “James Hutton and the Concept of a Dynamic Earth,” in C. J. Schneer, ed., Toward a History of Geology (Cambridge, Mass.-London, 1969). 122-141, provides a short summary and commentary on Hutton’s contributions to geology.

Anthologies of Hutton’s more important geological observations and conclusions, with commentaries, are J. Challinor, “The Early Progress of British Geology—III. From Hutton to Playfair, 1788-1802,” in Annals of Science, 10 (1954), 107-148; and D. A. Bassett, “James Hutton, the Founder of Modern Geology: An Anthology,” in Geology: The Journal of the Association of Teachers of Geology2 (1970), 55-76. S. I. Tomkeieff, “Uncomformity—an Historical Study,” in Proceedings of the Geologists’ Association, 73 (1962), 383-401, discusses Hutton’s use of unconformities as evidence for his geological theory.

Hutton’s contribution to geomorphology are discussed in E. B. Bailey, “The Interpretation of Scottish Scenery,” in Scottish Geographical Magazine, 50 (1934), 301-330; R. J. Chorley, A. J. Dunn, and R. P. Beckinsale, The History of the Study of Land Forms (London-New York, 1964); G. L. Davies, “The Eighteenth Century Denudation Dilemma and the Huttonian Theory of the Earth,” in Annals of Science, 22 (1966), 129-138; and “The Huttonian Earth-Machine,” in The Earth in Decay, a History of British Geomorphology 1578 to 1878 (London, 1969), ch. 6.

R. Hooykaas, Natural Law and Divine Miracle (Leide, 1959; 2nd ed., 1963), discusses Hutton’s geological theory in relation to the general theory of uniformitarianism. See also his paper “James Hutton und die Ewigkeit der Welt,” in Gesnerus, 23 (1966), 55-66.

V. A. Eyles, “A Bibliographical Note on the Earliest Printed Version of James Hutton’s Theory of the Earth, its Form and Date of Publication,” in Journal of the Society for the Bibliography of Natural History, 3 (1955), 105-108, gives the evidence establishing the authorship and date of publication of the Abstract, which was issued anonymously and undated.

The following commentaries refer to Hutton’s work in subject other than geology: J. R. Partington and D. McKie, “Histrorical Studies on the Phlogistgon Theory—III. Light and Heat in Combustion,” in Annuls of Sceience, 3 (1938), 366-370, analyzes Hutton’s views on the nature of phlogiston and concludes that his theory was almost indentical with that of A. Crawford; and P. A. Gerstner, “James Hutton’s Theory of the Earth and his Theory of Matter,” in Isis, 59 (1968), 26-31, and “The Reaction to James Hutton’s Use of Heat as a Geological Agent,” in British Journal of the History of Science, 5 (1971), 353-362, discusees Hutton’s ideas about heat and matter in relation to his theory of the earth.

Works on the development of science in the eighteenth and early nineteenth centuries that contain numerous references to Hutton are C. C. Gillispie, Genesis and Geology (Cambridge, Mass., 1951), particularly valuable for its very extensive bibliography; Loren Eiseley, Darwin’s Century (New York, 1958-London, 1959); and F. C. Haber. The Age of World (Baltomore, 1959).

The most frequently reproduced portrait of Hutton is the painting by the Scottish artist Sir Henry Raeburn. Two contemporary etchings are in A Series of Portrait and Caricature Etchings by the Late John Kay, 2 vols. (Edinburgh, 1837). A medallion portrait by the Scottish artist James Tassie is reproduced in the English trans. of K. A. von Zittle, History of Geology and Paleontology (London, 1901).

V. A. Eyles

HUTTON, JAMES

(b. Edinburgh, Scotland, United Kingdom 3 June 1726; d. Edinburgh, 26 March 1797)

geology, agriculture, physical sciences, philosophy. For the original article on Hutton see DSB, vol. 6.

Since the publication of Eyles’s article, several of Hutton’s major works have been reissued, including his doctoral dissertation (Donovan and Prentiss, 1980), the Abstract(1785/1987) (which Eyles drew on extensively), his Investigation of the Principles of Knowledge (1794/1999), and some of Hutton’s correspondence (Jones et al., 1994, 1995). A collection of colored drawings illustrating Hutton’s geotheory has been located and published (Craig et al., 1978). These were due to John Clerk of Eldin, Jr., or his father John Clerk of Eldin, also an artist friend of Hutton, who accompanied him on some of his geological excursions. They include a section by John Clerk Jr. showing Hutton’s idea of the likely structure of the large mass of granite in the Isle of Arran (Scotland), with a subterranean magma chamber and the strata adjacent to the granite upheaved by the igneous mass. Also, there are pictures of granitic veins penetrating the country rock at Glen Tilt, Perthshire, which supported Hutton’s theory. Dean’s republication of volume 3 of Hutton’s Theory of the Earth(1899/1997) provides access to his accounts of his fieldwork in the latter part of his career.

The secondary literature has emphasized the cyclic aspects of Hutton’s theory, his matter theory and its relationship to his geological theory, his economic interests, his agricultural interests and ideas on natural selection, his philosophical/methodological notions, and his religious views. Hutton has been the subject of an excellent intellectual biography (Dean, 1992). Drake (1981) has suggested that Hutton’s geotheory was significantly influenced by Robert Hooke, without acknowledgement.

Cyclic Theory and Unconformities; Geological Time . Hutton’s dissertation on the circulation of the blood (1749) contained the following passage:

Being about to treat of blood and bodily fluids, I shall, as far as possible, ignore solid materials in order to avoid digressions from the main subject-matter, although there exists so close a connection between those related items … that it is not easy to determine which of them has prior existence, both advancing in step, one refashioning the other and one modifying the other; and thus they display the glorious cycle of life and a very beautiful instance of perpetual moving—an instance in which matter moves without a material cause, in which it seeks its own special aims on the fertile earth, and in which it reconstitutes its daily diminutions by means of the very cause of its destruction; and before yielding its life-producing movement to the fatal necessity of material machines, it produces new offshoots, which will complete its role in the microcosmic grove. (Donovan and Prentiss, 1980, p. 30)

This early work suggests that Hutton was already thinking (teleologically) about cyclic processes, both in humans and in terrestrial cycles that sustain the Earth’s fertility. The hint of interest in agriculture and the machine analogy may also be remarked. Davies (1969) emphasized the importance of the steam engine (seen by Hutton when in Birmingham with James Watt in 1774, with all the movements generated by the action of a fire—almost as a perpetual motion machine!) as an analogical source for Hutton’s geotheory.

A remarkable feature of Hutton’s theory was that it was initially developed as a model or hypothesis, largely relying on the evidence of hand-specimens, and it was only after he had presented his ideas in 1785 that he embarked on a series of geological excursions specifically to find evidence that might support his theory. In particular, his journeys took him to the Isle of Arran near Glasgow (1787), where he saw the granite mountain, Goat Fell, with the surrounding sediments forming an eroded domed structure, and also a structural phenomenon at Lochranza that was later called an unconformity by Robert Jameson (one of Hutton’s opponents in Edinburgh). But a clearer example of an unconformity was observed and figured by the River Jed near Jedburgh, in the Scottish Border country, on Hutton’s return journey to Edinburgh. The river cutting showed horizontal layers of Old Red Sandstone, overlying vertical gritty sandstone—called “schistus” by Hutton (see Figure 1).

The events leading to the formation of such a structure could be construed according to Hutton’s theory as follows: deposition of sediments in the ocean; their compaction and consolidation, aided by subterranean heat, to form “schistus”; elevation and folding of strata by expansive subterranean forces; erosion of the now almost vertical strata of “schistus” to an approximately level surface; subsidence followed by deposition and consolidation of the sandstone strata now called Old Red Sandstone. The upward and downward movements were not fully explained, but the production of the sediments would have occurred by the erosion and weathering of neighboring higher ground. The contact between the vertical schistus and the horizontal Old Red Sandstone was the plane of unconformity and represented a large time-gap and break in the sedimentation. Given the slow processes of weathering, erosion, etc., the rocks obviously represented a huge amount of time, in human terms. Hutton’s overall theory may be summarized diagrammatically, as shown in Figure 2.

Later (1788) Hutton and two friends, John Playfair and Sir James Hall, sailed along the Berwickshire coast, looking for a contact similar to that at Jedburgh. Hutton knew that such rocks were in the vicinity, as his nearby upland farm was located on schistus while his lower farm was situated on Old Red Sandstone. The contact was found at a locality called Siccar Point, now famous in the annals of geology. Playfair (1805, p. 73) described his feelings on the occasion thus:

Revolutions still more remote appeared in the distance of this extraordinary perspective. The mind seemed to grow giddy by looking so far into the abyss of time; and while we listened with earnestness and admiration to the philosopher … unfolding to us the order and series of these wonderful events, we became sensible how much farther reason may sometimes go than imagination can venture to follow.

Thus theory and observations yielded a reasoned argument for the Earth’s antiquity. Evidence of two cycles of sedimentation could be seen directly. But there could or would have been untold earlier cycles. Time was needed for unconformities.

Chemical and Physical Aspects . But the source of terrestrial heat was mysterious. Hutton knew that plants required the Sun. Its light and warmth are called forms of radiant energy in the early twenty-first century. Hutton, however, talked about “solar substance.” Thus solar energy was regarded as a weightless “substance,” perhaps analogous to “caloric.” This “solar substance” might take various forms: “sensible” (or “specific”) heat, such as people feel when they touch a hot object; “latent” heat or the principle of fluidity, as discussed by Hutton’s friend Joseph Black; phlogiston; or electricity. Gerstner (1968) has suggested how, in his post–Siccar Point work, Hutton tried in his Dissertations on Different Subjects in Natural Philosophy(1792) to account for episodes of subsidence and consolidation of strata, and then expansion.

Hutton accepted Newtonian theory, particles being mutually attracted according to the inverse square law. But there could also be expansive forces, as exhibited in steam engines. So he imagined that if particles were pushed very close together, repulsive forces (a form of “solar substance”), acting according to some higher law than the square law, could begin to prevail, causing melting, expansion, and elevation of strata. There could be heat without fire. So Hutton sought to explain cycles of compression/heating, and expansion/elevation. His matter theory also supposedly allowed for the intrusion of subterranean matter, either as liquid or vapor. It is historically interesting that he tried to develop a physical theory to support his geological theory; but it led nowhere.

Hutton and Agriculture . Hutton spent a considerable time studying modern farming practices, and successfully improved his two farms in Berwickshire. Jones (1985) has pointed out how his experiences as a farmer would have shown the constant erosion of land and transport of sediments to the sea. Decayed plants helped renew the soil. Thus Hutton’s agricultural experience formed a background to his cyclic geotheory. Eyles mentioned that Hutton’s unpublished Principles of Agriculture contained ideas that foreshadowed Darwinian natural selection. Pearson (2003) has pointed out that such ideas also occurred in chapter 3 of the little-read 2,138-page, three-volume Investigation of the Principles of Knowledge. The following quotation illustrates:

if an organised body is not in the situation and circumstances best adapted to its sustenance and propagation, then, in conceiving an indefinite variety among the individuals of that species, >> those which depart most from the best adapted constitution, will be most liable to perish, while,… those organised bodies, which most approach to the best constitution for the present circumstances, will be best adapted to continue, in preserving themselves and multiplying …; their race. (2:501)

Hutton went on to talk about artificial selection (of dogs), the influence of the environment; and to all intents and purposes he entertained speciation. His words might well have been written by Darwin (which raises the question of whether Darwin picked up such ideas when he was studying in Edinburgh). Of course, Hutton’s geotheory would have allowed ample time for Darwinian evolution.

Hutton’s Philosophy and Method in Science . It is well known that Immanuel Kant developed a form of philosophical idealism, whereby the mind is regarded as an active agent in the acquisition of knowledge. It necessarily sees things in (Euclidean) space and (Newtonian) time and constructs and filters sensory information in terms of certain categories of the understanding. He proposed such ideas in response to problems raised by David Hume’s empiricism (e.g., the problem of induction).

It is striking that Hutton’s Principles of Knowledge(1794) developed a response to Hume somewhat analogous to Kant's, though almost certainly independently of him. For Hutton, like Kant, space and time are mere conceptions of the mind. Hume had offered an implausible account of human understanding of causal connections: It depended on habit. For example, one sees a billiard ball move whenever struck by another one, and one comes to suppose that it will always happen thus. Human understanding of causes and effects is, for Hume, simply a probabilistic extrapolation from empirically known instances. But Hutton wrote, in a Kantian manner:

[T]he knowledge of cause and effect, or the relation of things existing in succession, is discerned in the mind, where, without any form of an argument, a judgment is formed, or a new species of knowledge is produced, in an operation called reason. (1794, 2:188)

Observation per se does not discover cause. Ideas of necessary causal connection are the product of reasoning. Hutton, then, saw a radical difference between humans and “brutes” as regards wisdom. Insofar as an animal can reason, it does so without general principles. Also, only humans, not animals, can have moral principles inculcated.

Significantly, Hutton maintained that there had to be a first cause for everything, which he regarded as absolute, self-existing, efficient, and final. Knowledge of this was found by exercise of reason, not by the “superstitions” of religion. But while humans could recognize the existence of a first cause, they could not properly apprehend its nature:

[I]n the contemplation of this world, so beautiful is the order and arrangement of things, so plain and simple are the means, so deep and complicated the design, so secret every cause, and so certain the effect, we must conclude that nothing but a wisdom without defect had been employed, and that such wisdom is infinite or incomprehensible to man. (1794, 3: 645)

So, for Hutton, the universe was, as he put it, ordained in perfect wisdom. He was a teleologist and a deist.

These ideas were formally expressed in Hutton’s technical philosophy after his geological fieldwork ended, but they underpinned his geology, and probably derived in part from his agricultural experience. Erosion was continuous, spoiling the farmer’s circumstances. But the world—supposedly designed in wisdom—had its soils naturally replenished. Hutton’s geotheory explained how the design was maintained. This avoided what has been called the “denudation dilemma” (Davies, 1969, p. 160) or the “paradox of the soil” (Gould, 1987, p. 76). There was a wise adaptation of means to ends.

Although Hutton’s philosophy had quasi - Kantian features, in fact, it stood essentially within the British empiricism tradition of John Locke, George Berkeley, and Hume. He was not saying (à la Kant) that notions of space and time are intrinsic faculties of the mind—necessary conditions for experience. They were, rather, abstracted from experience. But having acquired the notion of time experientially, the geologist could look into the past and try to understand it. With a cyclic geotheory, there was a nice interplay of contemporary experiences (e.g., soil erosion) and past changes on the Earth. So Hutton had a philosophical warrant for what was later known as actualism or methodological uniformitarianism (“the present is the key to the past,” Geikie [1962, p. 299]).

There has, then, been discussion as to whether Hutton’s geology was a priori and teleological or had an empirical base. Was he a hypothetico-deductivist or an inductivist/empiricist? Which came first: the philosophy or the observations? The former alternative has been advocated particularly by Gould (1987, p. 76), who stated that “Hutton present[ed] his theory as the a priori solution to a problem in causation, not as an induction from the field evidence.” That is, philosophy and theory came first, and only then was the theory tested in the field. Dean (1992), however, has argued, against Gould, that there was a development of Hutton’s ideas over time, so that he did not simply invent his theory a priori in his early years and then spend the rest of his time seeking to test it by observation. The two interpretations have been examined by Leveson (1996), who concluded that Hutton’s inductivism was not without foundation but needed to be interpreted with caution. Hutton was, in fact, a hypothetico-deductivist. To which one might add that it did not matter pragmatically whether the theory came from Hutton’s epistemology, his deism, the Aristotelian notion of final causes, or acceptance of the world as manifesting divine wisdom, or whatever. The theory did lead to certain observational expectations, and these were mostly fulfilled.

Hutton’s Religious Views . şengör (2001) has suggested that Hutton was an atheist, but that in the context of eighteenth-century Edinburgh he did not choose to reveal

this. It is certainly accepted that Hutton lost any conventional Christian faith early, having encountered deism while a student via the mathematics lecturer Colin Maclaurin. It is hard to agree withşengör’s suggestion, however, given the enormous effort involved in writing the Principles of Knowledge, according to which humankind could derive delight from contemplating the universe “so beautifully calculated.” And such limited wisdom as humans possess derives from a higher cause: “we do not exist independent of our author, who is the cause of us, and of the faculties in which we exist; and it is only in knowing this, that we know there is, in God, both intellect and truth” (1794, 3:198–199). Hutton evidently had a reasoned faith.

Founder of Modern Geology? . Hutton has often been regarded as the “founder of modern geology” (e.g., Dean, 1992, p. 1). But in his examination of the origins of geology as a historical science, Martin Rudwick (2005) suggests that Hutton’s work came at the end—perhaps the culmination—of the older tradition of theories of the Earth, or “geotheory,” to use Rudwick’s preferred term.

Rudwick sees the emergence of geology as involving “bursting the limits of time” (which Hutton surely did) and the study of the Earth as an object with a contingent history, which could be unraveled chiefly with the help of biostratigraphy. Hutton’s doctrine of unlimited repetitive cycles, lacking any direction, was not, for Rudwick, the stuff of the new geology at the turn of the nineteenth century, with Cuvier as the leading light. Certainly, Hutton was not a stratigrapher, and his cyclism gave less scope for historical contingencies than did Cuvier’s unidirectional geohistory. But in his Theory of the Earth (1795, 1:363) he wrote:

[N]ature, forming strata, is subject to vicissitudes; and … [there] is not always the same regular operation with respect to the materials, although always forming strata upon the same principles. Consequently, upon the same spot in the sea, different materials may be accumulated at different periods of time, and, conversely, the same or similar materials may be collected in different places at the same time.

This implies that things would not necessarily be the same from one geocycle to the next; therefore, even if one defines geology to be a historical science, requiring the examination of different contingent states of affairs through time, Hutton’s geology would be compatible with that definition. And his cyclic theory, for all its problems, gave investigators a basic understanding of the Earth that has survived to the present—alongside biostratigraphy and much else besides. It seems reasonable to regard Hutton as at least a founder of modern geology, his eighteenth-century metaphysical basis notwithstanding.

SUPPLEMENTARY BIBLIOGRAPHY

WORKS BY HUTTON

James Hutton’s Theory of the Earth: The Lost Drawings, edited by Gordon Y. Craig, Donald B. McIntyre, and Charles D. Waterston. Edinburgh: Scottish Academic Press, 1978.

James Hutton’s Medical Dissertation, edited by Arthur Donovan and Joseph Prentiss. Transactions of the American Philosophical Society, vol. 70, part 6. Philadelphia: American Philosophical Society, 1980.

The 1785 Abstract of James Hutton’s Theory of the Earth, introduction by G. Y. Craig. Edinburgh: Scottish Academic Press, 1987.

Dissertations on Different Subjects in Natural Philosophy. Edinburgh: A. Strahan and T. Cadell, 1792.

An Investigation of the Principles of Knowledge and of the Progress of Reason, from Sense to Science and Philosophy, with a new Introduction by Jean Jones and Peter Jones. 3 vols. Bristol: Thoemmes Press, 1999. Facsimile reprint of the 1794 edition of Strahan and Cadell.

Theory of the Earth: With Proofs and Illustrations. 3 vols. Edinburgh: Cadell, Davies, and Creech, 1795–1899.

James Hutton in the Field and in the Study: Being an Augmented Reprinting of Vol. III of Hutton's Theory of the Earth (I, II, 1795), as First Published by Sir Archibald Geikie (1899); A Bicentenary Tribute to the Father of Modern Geology, edited by Dennis R. Dean. Delmar, NY: Scholars’ Facsimiles and Reprints, 1997.

OTHER SOURCES

Allchin, Douglas. “James Hutton and Phlogiston.” Annals of Science 51 (1994): 615–635.

Davies, Gordon L. “The Huttonian Earth-Machine 1785–1802.” In The Earth in Decay: A History of British Geomorphology, 1578–1878, by Gordon L. Davies. London: Macdonald Technical and Scientific, 1969.

Dean, Dennis R. James Hutton and the History of Geology. Ithaca, NY: Cornell University Press, 1992.

———. “Hutton Scholarship, 1992–1997.” In James Hutton— Present and Future, edited by Gordon Y. Craig and John H. Hull. London: The Geological Society, 1999.

Drake, Ellen Tan. “The Hooke Imprint on the Huttonian Theory.” American Journal of Science 281 (September 1981): 963–973.

Donovan, Arthur L. “James Hutton, Joseph Black, and the Chemical Theory of Heat.” Ambix 25 (1978): 176–180.

Geikie, Sir Archibald. The Founders of Geology. 2nd edition. New York: Dover Publications, 1962 (reprint of Macmillan, 1905).

Gerstner, Patsy A. “James Hutton’s Theory of the Earth and His Theory of Matter.” Isis 59 (1968): 26–31.

Gould, Stephen J. Time’s Arrow, Time’s Cycle. Cambridge, MA: Harvard University Press, 1987.

Jones, Jean. “James Hutton’s Agricultural Research and His Life as a Farmer.” Annals of Science 42 (1985): 574–601.

———, Eric Robinson, and Hugh S. Torrens. “The Correspondence between James Hutton (1726–1797) and James Watt (1736–1819) with Two Letters from Hutton to George Clerk-Maxwell (1715–1784).” Annals of Science 51 (1994): 637–653; 52 (1995): 357–382.

Jones, Peter. “An Outline of the Philosophy of James Hutton (1726–97).” In Philosophers of the Scottish Enlightenment, edited by Vincent Hope. Edinburgh: Edinburgh University Press, 1984.

Leveson, David J. “What Was Hutton’s Methodology?” Archives of Natural History 23 (1996): 61–77.

McIntyre, Donald B. “James Hutton’s Edinburgh: The Historical, Social, and Political Background.” Earth Sciences History 16 (1997): 100–157.

O’Rourke, Joseph. “A Comparison of James Hutton’s Principles of Knowledge and Theory of the Earth.” Isis 69 (1978): 5–20.

Pearson, Paul N. “In Retrospect: An Investigation of the Principles of Knowledge and the Progress of Reason, from Sense to Science and Philosophy by James Hutton 1794.” Nature 425 (2003): 665.

Playfair, John. “Biographical Account of the Late Dr James Hutton, F. R. S. Edin.” Transactions of the Royal Society of Edinburgh 5, part 3 (1805): 39–99.

Rudwick, Martin J. S. Bursting the Limits of Time: The Reconstruction of Geohistory in the Age of Revolution. Chicago: University of Chicago Press, 2005.

şengör, A. M. Celâl. Is the Present the Key to the Past or Is the Past the Key to the Present? James Hutton and Adam Smith versus Abraham Gottlob Werner and Karl Marx in Interpreting History. Geological Society of America Special Paper 355. Boulder, CO: Geological Society of America, 2001.

David Oldroyd

James Hutton

The Scottish naturalist James Hutton (1726-1797), the founder of modern geology, is best known for his Theory of the Earth.

James Hutton was born in Edinburgh on June 3, 1726. He entered Edinburgh University in 1740 to study the humanities, but he developed an intense and long-lasting interest in chemistry. At 17 Hutton was placed as an apprentice in a lawyer's office; however, performing chemistry experiments during office hours led to his dismissal, and he then chose medicine as a profession. For 3 years he pursued medical studies at Edinburgh University in spite of the fact that no degree of medicine could be obtained from that institution. Therefore, in 1747 he went to Paris to study chemistry and anatomy. He received a medical degree at Leiden in 1749.

Back in London, Hutton realized that even medicine would not give him sufficient spare time for his scientific interests. He therefore abandoned medicine for agriculture. In 1752 he went to a farm in Norfolk, where the scenery apparently turned his mind to mineralogy and geology.

Theory of the Earth

In 1754 Hutton visited Flanders allegedly to compare husbandry methods with those practiced in Norfolk. Actually he spent most of his time making geological observations later to be included in his Theory of the Earth. At the end of the year he settled down at his family property in Berwickshire, where he managed a farm according to the most scientific methods. In 1768 he abandoned his country life and settled in Edinburgh, spending all his time on scientific studies. His interests, however, were by no means confined to geology, for he published treatises on physics and metaphysics and investigated all branches of science except mathematics.

The spectacular geological features around Edinburgh provided Hutton with numerous fundamental observations to combine with his broad knowledge of many parts of Great Britain. Eventually he was led to formulate a definite theory, or system, of the earth, and although he had discussed it at length with his friends, he did not write it down until he was persuaded to address in 1785 one of the first meetings of the newly founded Royal Society of Edinburgh. The full text was published in the Transactions in 1788 under the title "Theory of the Earth; or, An Investigation of the Laws Observable in the Composition, Dissolution and Restoration of Land upon the Globe." The paper attracted little attention, perhaps because of its misleading title of "Theory" and its publication in the transactions of a learned society which had just been founded. However, when the paper was criticized in 1793, Hutton revised and developed his theory in greater detail. The result was the Theory of the Earth, with Proofs and Illustrations (2 vols., 1795). A projected third volume remained incomplete and was published by the Geological Society of London in 1899.

Hutton's Doctrine

In Hutton's opinion, the purpose of geology is first to collect objective data by observing the earth's crust and second to interpret the evidence with a minimum amount of imagination, rather than to begin with an artificial hypothesis and then attempt to fit the observations into a rigid theoretical framework. Hutton's theory evolved in such a natural fashion from his observations that it achieved the prerequisite of involving very little speculation. His basic assumption is that the past history of the globe should be interpreted in the light of what is happening today or has happened in recent times. This dominant idea that the present is the key to the past is so commonplace in modern geological thinking that one often fails to fully appreciate the genius of the man who first formulated it in modern times.

Hutton first turned his attention to sedimentary rocks, observing that they consist of debris of older rocks. He drew a parallel between such rocks and present-day marine deposits, comparing conglomerates with gravels, sandstones with sands, limestones with accumulations of organic debris, and shales with silts and muds. From the wide distribution of these beds—which form the continents—he understood that they could only have been deposited in the sea. Hutton's first conclusion was that the continents consisted of indurated sediments which, eroded from some preexisting emerged land, had been spread in strata over the sea floor. Since all these sedimentary rocks were originally deposited as soft sediments but appear today as indurated rocks, he attributed this change to the combined action of pressure and subterranean heat.

Hutton's next problem was to explain how beds originally deposited in a horizontal fashion on the sea floor could occur in mountains such as the Alps, tilted, ruptured, and contorted in a spectacular fashion. Hutton understood that such occurrences resulted from powerful revolutions which at different times in the past seem to have affected the entire earth's crust. After having demonstrated the existence of episodes of large-scale deformation which had uplifted the sea bottom with its indurated sediments and folded them in a complex manner to build the existing continents, he investigated the possible cause of these processes. He assumed the existence of forces acting vertically and upward which were probably related to deep-seated reservoirs of heat. The action of these vertical forces interfering with gravity and the resistance of the rocks would create a lateral and oblique component responsible for the contortions of the beds.

Hutton considered volcanoes as safety valves through which some of the earth's internal heat could escape, but he understood that the heat was not due to the combustion of coal seams or the oxidation of pyritic shales, as believed for a long time, but to a deep-seated and molten mass. By means of this concept, Hutton attempted to explain the origin of the various types of nonstratified rocks, either massive or in veins, which he had observed in different places. He called them whinstones (basic rocks, including basalts), porphyries, and granites, and interpreted them as material that once had been in a molten condition and subsequently had been injected upward during the great disturbances of the earth's crust.

Most of the modern ideas on geomorphology are to be found in the Huttonian theory, including the importance of the erosion and transportation power of mountain glaciers. However, these concepts were ignored or even rejected for many years.

Hutton died on March 26, 1797. His Theory of the Earth is marred by a rather obscure style and defective organization. One of his friends, John Playfair, the mathematician and natural philosopher, was able to give the work a well-organized and elegant presentation, combined with a series of personal comments, under the title Illustrations of the Huttonian Theory of the Earth (1802).

Further Reading

A modern biography of Hutton, including excerpts of his major works, is Edward Battersby Bailey, James Hutton: The Founder of Modern Geology (1967). Other accounts of Hutton's life and contribution to geology are in Sir Archibald Geikie, The Founders of Geology (1897; 2d ed. 1905); Karl Alfred von Zittel, History of Geology and Palaeontology to the End of the Nineteenth Century (1899; trans. 1901); and F. D. Adams, The Birth and Development of the Geological Sciences (1938). □

James Hutton

1726-1797

Scottish Geologist and Chemist

James Hutton was born in Edinburgh, Scotland, in 1726. There was no early indication that this quiet, modest boy would achieve worldwide renown and secure his place in history as "the father of modern geology." With no corroborating data or earlier research to support his conclusions, his personal observations generated the concept of the "rock cycle," which—in three stages—shows that the matter of which rocks are made is never created or destroyed. It simply is redistributed and transformed from one type to another in an eternal recycling manner. This principle, called "uniformitarianism," is one of the foundations of modern geology.

This futuristic thinking matured over many years of study and field work that began when Hutton attended the University of Edinburgh, initially to study the law. He soon abandoned this pursuit for medicine and studied in both Paris, France, and Leiden, Holland. He earned his doctorate in Leiden but never actually practiced medicine.

He returned to Edinburgh to pursue an earlier interest in chemistry, which he had shared with his friend James Davie. The pair had investigated the possibilities of manufacturing sal ammoniac from coal soot in an inexpensive manner and decided to market the resulting product. The results were so successful that Hutton was soon a prosperous, independently wealthy man.

He used part of his fortune to become a gentleman farmer in Berwickshire, England. With this second good source of income at hand, he gave up active farming and returned to Edinburgh, where he planned to devote himself to scientific research—especially in the area of soil, rocks, and the natural processes that altered their appearance and locations.

Hutton was among the first researchers who made a cycle connection between the three known types of rock: igneous, sedimentary, and metamorphic. His observations were published in two papers in 1788 and later in the book Theory of Earth (1795). Unfortunately, Hutton was a far better scientist than author, and his 1795 book was not truly appreciated until it was explained, amplified, and supported by his friend John Playfair in 1802, when the latter published Illustrations of the Huttonian Theory of the Earth. In this work Playfair elaborated on the theme that eventually became fundamental to the world of geology: deep time. This was a phenomenal concept that centered on "Unconformity," the visual evidence of a loss of sedimentary layers that indicate a loss of geologic time.

Hutton described Earth as a self-renewing, eternal recycling machine that continues to renew itself in three distinct stages. Stage one is the inevitable decay resulting from the erosion caused by rivers, waves, and tides that wash the soils of the continents into the oceans, creating stage two: layers of sediment that build upon each other. The increasing weight of these layers precipitates stage three: the heating and melting of the sediments, thus producing magmas that generate intolerable heat forces. These forces in turn result in "uplifts": earthquakes, volcanoes, and other catastrophic actions that form new continents, islands, and other surface transformations.

This, of course, is a highly simplified version of Hutton's theories and observations. To this date, there are still thousands of pages he authored that have never been printed (or even translated, since he wrote in French much of the time). However, the impact of his work is still highly regarded and is part of the coursework in most geological curriculums. His contributions to the field receive high acclaim from notable authors and evolutionary biologists such as Stephen Jay Gould (1941-), whose Time's Arrow, Time's Cycle (1987) praises Hutton generously.

During the eighteenth century when Hutton came to his amazing conclusions, there was no way of proving the existence of the vast expanses of time in a geological sense. It was not until the twentieth century that scientists (specifically chemists) were able to use radioactive decay in estimating the ages of rocks and other ancient discoveries.

James Hutton died in 1797, leaving a staggering amount of written material to support his field work and studies. The last two sentences of one of his pioneering 1788 treatises have guaranteed him his rightful place at the top of the geological pyramid: "If the succession of worlds is established in the system of nature, it is in vain to look for anything higher in the origin of the earth. The result, therefore, of our present enquiry is, that we find no vestige of a beginning—no prospect of an end."

BROOK HALL

Hutton, James

Scottish Geologist
1726–1797

James Hutton was from Scotland and is considered to be the founder of modern geology. After a successful career as a farmer and chemist, he retired at the age of 42 in 1768 to devote the rest of his life to geology. He traveled widely, studying rocks and the processes that formed them.

He presented his "Theory of the Earth" to the Royal Society of Edinburgh in 1785. This was later developed into a book with a similar title in 1795. The book was not well written and did not achieve impact until a book written by a friend and colleague, John Playfair, "Illustrations of the Huttonian Theory of the Earth," was published in 1802. It was a clear presentation of Hutton's ideas, and ultimately was used as the basis for geological theory.

Two Geological Concepts

In James Hutton's time, much knowledge had been gathered about rocks, fossils, and strata, but it had not been synthesized into a theory of geologic time. Progress was impeded by the "catastrophism" belief of most geologists that the Earth was about 6,000 years old, based on the Biblical notion that most rocks had precipitated from Noah's flood. Hutton held that tremendous periods of time were required to gradually form landscapes and erode them, and the Earth therefore was immensely old.

Hutton achieved two major fundamental ideas that have become foundations of modern geology. The first idea is the doctrine of uniformitarianism. He stated that geologic phenomena can be explained in terms of observable processes which have been at work for long periods of time. The physical geological processes operating today also operated in the past; hence, to learn how rocks were formed in the past, one must study those processes today. "The present is the key to the past" summarizes this thought.

A second idea is the cycle of landscape development. Ordinary processes, which may appear small, yet operating over long intervals of time, can form great changes—as great as those from catastrophic events. Hutton said that mountains are exposed to water and air, and the rocks weather. The landscape is worn down as water erodes the sediments from the rocks and transports them to the sea for deposition. These are eventually compacted and cemented to form sedimentary rocks. Subterranean heat resulting from "plutonism" (deep-seated igneous processes) causes upheaval of the sediments, and mountains are formed, beginning the whole cycle again.

see also Erosion and Sedimentation; Fresh Water, Physics and Chemistry of; Garrels, Robert; Stream Erosion and Landscape Development; Weathering of Rocks.

Scott F. Burns

Bibliography

Porter, R. The Making of Geology—Earth Science in Britain 1660–1850. Cambridge, U.K.: Cambridge University Press, 1977.