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History of Civilization in England, Vol. 3 of 3
783
‘The execution of his map was completed in 1815, and remains a lasting monument of original talent and extraordinary perseverance; for he had explored the whole country on foot without the guidance of previous observers, or the aid of fellow-labourers, and had succeeded in throwing into natural divisions the whole complicated series of British rocks.’ Lyell's Principles of Geology, p. 58. Geological maps of parts of England had, however, been published before 1815. See Conybeare on Geology, in Second Report of the British Association, p. 373.
784
‘A great body of new data were required; and the Geological Society of London, founded in 1807, conduced greatly to the attainment of this desirable end. To multiply and record observations, and patiently to await the result at some future period, was the object proposed by them; and it was their favourite maxim, that the time was not yet come for a general system of geology, but that all must be content for many years to be exclusively engaged in furnishing materials for future generalizations.’ Lyell's Principles of Geology, p. 59. Compare Richardson's Geology, 1851, p. 40.
785
Cuvier, in his Life of Werner, says (Biographie Universelle, vol. i. pp. 376, 377), ‘La connaissance des positions respectives des minéraux dans la croûte du globe, et ce que l'on peut en conclure relativement aux époques de leur origine, forment une autre branche de la science qu'il appelle Géognosie. Il en présenta les premières bases en 1787, dans un petit écrit intitulé “Classification et description des Montagnes.”’
786
Whewell's History of the Inductive Sciences, vol. iii. p. 567.
787
‘Une mer universelle et tranquille dépose en grandes masses les roches primitives, roches nettement cristallisées, où domine d'abord la silice. Le granit fait la base de tout; au granit succède le gneiss, qui n'est qu'un granit commençant à se feuilleter.’ … ‘Des agitations intestines du liquide détruisent une partie de ces premiers dépôts; de nouvelles roches se forment de leurs débris réunis par des cimens. C'est parmi ces tempêtes que naît la vie.’ … ‘Les eaux, de nouveau tranquillisées, mais dont le contenu a changé, déposent des couches moins épaisses et plus variées, où les débris des corps vivans s'accumulent successivement dans un ordre non moins fixe que celui des roches qui les contiennent. Enfin, la dernière retraite des eaux répand sur le continent d'immenses alluvions de matières meubles, premiers sièges de la végétation, de la culture et de la sociabilité.’ Eloge de Werner, in Cuvier, Recueil des Elogés Historiques, vol. ii. pp. 321–323.
788
‘If it be true that delivery be the first, second, and third requisite in a popular orator, it is no less certain that to travel is of first, second, and third importance to those who desire to originate just and comprehensive views concerning the structure of our globe. Now, Werner had not travelled to distant countries: he had merely explored a small portion of Germany, and conceived, and persuaded others to believe, that the whole surface of our planet, and all the mountain chains in the world, were made after the model of his own province.’ … ‘It now appears that he had misinterpreted many of the most important appearances even in the immediate neighbourhood of Freyberg. Thus, for example, within a day's journey of his school, the porphyry, called by him primitive, has been found not only to send forth veins, or dykes, through strata of the coal formation, but to overlie them in mass.’ Lyell's Principles of Geology, p. 47.
789
Though Hutton's Theory of the Earth was first published in 1788, the edition of 1795, which is the one I have used, contains a great number of additional illustrations of his views, and was evidently re-written. But the main features are the same; and we learn from his friend, Playfair, that ‘the great outline of his system’ was completed ‘several years’ before 1788. Life of Hutton, in Playfair's Works, vol. iv. p. 50, Edinburgh, 1822.
790
Kirwan appears to have been the first who called Hutton's theory ‘the Plutonic System.’ See Illustrations of the Huttonian Theory, in Playfair's Works, vol. i. p. 145. On the distinction between Neptunists and Plutonists, see the same work, pp. 504, 505.
791
‘Has not only supplanted that of Werner, but has formed the foundation of the researches and writings of our most enlightened observers, and is justly regarded as the basis of all sound geology at the present day.’ Richardson's Geology, London, 1851, p. 38.
792
Hutton's Theory of the Earth, Edinb. 1795, vol. i. pp. 34, 41, 192, 290, 291, 593, vol. ii. pp. 236, 369, 378, 555.
793
‘In his writings, and in those of his illustrator, Playfair, we find the germ of the metamorphic theory.’ Lyell's Manual of Geology, London, 1851, p. 92.
794
The shortest summary of this view is in his Theory of the Earth, Edin. 1795, vol. ii. pp. 556. ‘The doctrine, therefore, of our Theory is briefly this; that whatever may have been the operation of dissolving water, and the chemical action of it upon the materials accumulated at the bottom of the sea, the general solidity of that mass of earth, and the placing of it in the atmosphere above the surface of the sea, has been the immediate operation of fire or heat melting and expanding bodies.’
795
‘Although Hutton had never explored any region of active volcanos, he had convinced himself that basalt and many other trap rocks were of igneous origin.’ Lyell's Principles of Geology, London, 1853, p. 51. To this I may add, that he wrote his work without having examined granite. He says (Theory of the Earth, vol. i. p. 214), ‘It is true, I met with it on my return by the east coast, when I just saw it, and no more, at Peterhead and Aberdeen; but that was all the granite I had ever seen when I wrote my Theory of the Earth. I have, since that time, seen it in different places; because I went on purpose to examine it, as I shall have occasion to describe in the course of this work.’ Hutton's theory of granite is noticed in Bakewell's Geology, London, 1838, p. 101: but Mr. Bakewell does not seem to be aware that the theory was formed before the observations were made.
796
Huttonian Theory, in Playfair, vol. i. pp. 38–40, 509, 510. Compare Playfair's Life of Hutton, p. 61.
797
Hence, the objections of Kirwan were invalid; because his argument against Hutton was ‘grounded on experiments, where that very separation of the volatile and fixed parts takes place, which it excluded in that hypothesis of subterraneous heat.’ Huttonian Theory, in Playfair, vol. i. p. 193, Edinb. 1822.
798
Hutton says (Theory of the Earth, Edinb. 1795, vol. i. p. 94), ‘The place of mineral operations is not on the surface of the earth; and we are not to limit nature with our imbecility, or estimate the powers of nature by the measure of our own.’ See also p. 159, ‘mineral operations proper to the lower regions of the earth.’ And p. 527, ‘The mineral operations of nature lie in a part of the globe which is necessarily inaccessible to man, and where the powers of nature act under very different conditions from those which we find take place in the only situation where we can live.’ Again, in vol. ii. p. 97, ‘The present Theory of the Earth holds for principle that the strata are consolidated in the mineral regions far beyond the reach of human observation.’ Similarly, vol. ii. p. 484, ‘we judge not of the progress of things from the actual operations of the surface.’
799
Hutton, however, did not believe that this could be done. ‘In the Theory of the Earth which was published, I was anxious to warn the reader against the notion that subterraneous heat and fusion could be compared with that which we induce by our chemical operations on mineral substances here upon the surface of the earth.’ Hutton's Theory of the Earth, vol. i. p. 251.
800
See, in the Life of Hutton, in Playfair's Works, vol. iv. p. 62 note, a curious remark on his indifference to experimental verification. Innumerable passages in his work indicate this tendency, and show his desire to reason immediately from general principles. Thus, in vol. i. p. 17, ‘Let us strictly examine our principles in order to avoid fallacy in our reasoning.’ … ‘We are now, in reasoning from principles, come to a point decisive of the question.’ vol. i. p. 177. ‘Let us now reason from our principles.’ vol. ii. p. 308. Hence, his constantly expressed contempt for experience; as in vol. ii. p. 367, where he says that we must ‘overcome those prejudices which contracted views of nature and magnified opinions of the experience of man may have begotten.’
801
Playfair (Life of Hutton, p. 64) says that it drew ‘their attention’ (i. e. the attention of ‘men of science’), ‘very slowly, so that several years elapsed before any one showed himself publicly concerned about it, either as an enemy or a friend.’ He adds, as one of the reasons of this, that it contained ‘too little detail of facts for a system which involved so much that was new, and opposite to the opinions generally received.’
802
The account of these experiments was read before the Royal Society of Edinburgh in 1805, and is printed in their Transactions, vol. vi. pp. 71–185, Edinb. 1812, 4to. The general result was (pp. 148, 149), ‘That a pressure of 52 atmospheres, or 1700 feet of sea, is capable of forming a limestone in a proper heat; That under 86 atmospheres, answering nearly to 3000 feet, or about half a mile, a complete marble may be formed; and lastly, That, with a pressure of 173 atmospheres, or 5700 feet, that is little more than one mile of sea, the carbonate of lime is made to undergo complete fusion, and to act powerfully on other earths.’ See also p. 160: ‘The carbonic acid of limestone cannot be constrained in heat by a pressure less than that of 1708 feet of sea.’ There is a short, and not very accurate, notice of these instructive experiments in Bakewell's Geology, London, 1838, pp. 249, 250.
803
As Sir James Hall says, ‘The truth of the most doubtful principle which Dr. Hutton has assumed, has thus been established by direct experiment.’ Transactions of the Royal Society of Edinburgh, vol. vi. p. 175.
804
See the remarks of Sir James Hall, in Transactions, vol. vi. pp. 74, 75. He observes that Hutton's ‘system, however, involves so many suppositions, apparently in contradiction to common experience, which meet us on the very threshold, that most men have hitherto been deterred from an investigation of its principles, and only a few individuals have justly appreciated its merits.’ … ‘I conceived that the chemical effects ascribed by him to compression, ought, in the first place, to be investigated.’ … ‘It occurred to me that this principle was susceptible of being established in a direct manner by experiment, and I urged him to make the attempt; but he always rejected this proposal, on account of the immensity of the natural agents, whose operation he supposed to lie far beyond the reach of our imitation; and he seemed to imagine that any such attempt must undoubtedly fail, and thus throw discredit on opinions, already sufficiently established, as he conceived, on other principles.’
805
It may be traced back, certainly to the beginning of the seventeenth century, and probably still higher. Yet the popular opinion seems to be correct, that Watt was its real inventor; though, of course, he could not have done what he did, without his predecessors. This, however, may be said of all the most eminent and successful men, as well as of the most ordinary men.
806
On the obligations of Watt to Black, compare Brougham's Life of Watt (Brougham's Works, vol. i. pp. 25, 36–38, edit. Glasgow, 1855), with Muirhead's Life of Watt, second edit. London, 1859, pp. 66, 83. At p. 301, Mr. Muirhead says of Watt, that ‘his principal inventions connected with the steam-engine, with all their prodigious results, were founded, as we have seen, on the attentive observation of great philosophical truths; and the economy of fuel, increase of productive power, and saving of animal labour, which gradually ensued, all originated in the sagacious and careful thought with which he investigated the nature and properties of heat.’ But whatever investigations Watt made into heat, he discovered no new law respecting it, or, at all events, no new law which is large enough to be noted in the history of thermotics, considered purely as a science, and apart from practical application. Mr. Muirhead, in his interesting work which I have just quoted, has published (pp. 484–486) some remarks made on the subject by Watt, several years after the death of Black, which, though perfectly fair and candid, show that Watt had a rather confused notion of the real difference between an invention and a discovery.
807
Mr. Muirhead, in his Life of Watt, pp. 301–370, seems to have put the priority of Watt beyond further doubt; though he is somewhat hard upon Cavendish, who, there can be little question, made the discovery for himself.
808
I would not wish to diminish one jot of the veneration in which the great name of Watt is justly held. But when I find the opinion of Dr. Withering, the botanist, quoted, to the effect that his ‘abilities and acquirements placed him next, if not superior, to Newton.’ (Muirhead's Life of Watt, p. 302), I cannot but protest against such indiscriminate eulogy, which would rank Watt in the same class as one of those godlike intellects of which the whole world has not produced a score, and which are entitled to be termed inspired, if ever human being was so. Another instance of this injudicious panegyric will be found in the same otherwise excellent work (Muirhead, pp. 324, 325), where we read that Watt's discovery that water consists of oxygen and hydrogen, was ‘the commencement of a new era, the dawn of a new day in physical inquiry, the real foundation of the new system of chemistry; nay, even a discovery “perhaps of greater importance than any single fact which human ingenuity has ascertained either before or since.”’
809
That there was no plagiarism on the part of Watt, we know from positive evidence; that there was none on the part of Cavendish, may be fairly presumed, both from the character of the man, and also from the fact that in the then state of chemical knowledge the discovery was imminent, and could not have been long delayed. It was antecedently probable that the composition of water would be ascertained by different persons at the same time, as we have seen in many other discoveries which have been simultaneously made, when the human mind, in that particular department of inquiry, had reached a certain point. We are too apt to suspect philosophers of stealing from each other, what their own abilities are sufficient to work out for themselves. It is, however, certain that Watt thought himself ill-treated by Cavendish. See Watt's Correspondence on the Composition of Water, London, 1846, pp. 48, 61.
810
On 26th November 1783, he writes: ‘For many years I have entertained an opinion that air was a modification of water; which was originally founded on the facts, that in most cases where air was actually made, which should be distinguished from those wherein it is only extricated from substances containing it in their pores, or otherwise united to them in the state of air, the substances were such as were known to contain water as one of their constituent parts, yet no water was obtained in the processes, except what was known to be only loosely connected with them, such as the water of the crystallization of salts. This opinion arose from a discovery that the latent heat contained in steam diminished, in proportion as the sensible heat of the water from which it was produced, increased; or, in other words, that the latent heat of steam was less when it was produced under a greater pressure, or in a more dense state, and greater when it was produced under a less pressure, or in a less dense state; which led me to conclude, that when a very great degree of heat was necessary for the production of the steam, the latent heat would be wholly changed into sensible heat; and that, in such cases, the steam itself might suffer some remarkable change. I now abandon this opinion, in so far as relates to the change of water into air, as I think that may be accounted for on better principles.’ See this remarkable passage, which is quite decisive as to the real history of Watt's discovery, in Correspondence of James Watt on the Composition of Water, London, 1846, pp. 84, 85. Compare p. cxxiv. and p. 248 note.
811
In the paper which he communicated to the Royal Society, announcing his discovery, he, well knowing the empirical character of the English mind, apologizes for this; and says, ‘I feel much reluctance to lay my thoughts on these subjects before the public in their present indigested state, and without having been able to bring them to the test of such experiments as would confirm or refute them.’ Watt's Correspondence on the Discovery of the Composition of Water, pp. 77, 78. Eleven months earlier, that is in December 1782, he writes (Ibid. p. 4): ‘Dr. Priestley has made a most surprising discovery, which seems to confirm my theory of water's undergoing some very remarkable change at the point where all its latent heat would be changed into sensible heat.’
812
‘He’ (i. e. Cavendish) ‘here omits entirely the consideration of latent heat; an omission which he even attempts to justify, in one of the passages interpolated by Blagden. But it is well known to every one acquainted with the first principles of chemical science, even as it was taught in the days of Black, and it was indisputably familiar to Mr. Watt, that no aëriform fluid can be converted into a liquid, nor any liquid into a solid, without tho evolution of heat, previously latent. This essential part of the process, Mr. Cavendish's theory does not embrace; but without it, no theory on the subject can be complete; and it will presently be seen, that Mr. Watt took it fully into account.’ Muirhead's Life of Watt, p. 315.
813
‘Cavendish and Watt both discovered the composition of water. Cavendish established the facts; Watt the idea.’ … ‘The attaching too high a value to the mere facts, is often a sign of a want of ideas.’ Liebig's Letters on Chemistry, London, 1851, p. 48. The last sentence of this illustrious philosopher, which I have put in italics, should be well pondered in England. If I had my way, it should be engraved in letters of gold over the portals of the Royal Society and of the Royal Institution.
814
‘Organic substances, whether directly derived from the vegetable or animal kingdom, or produced by the subsequent modification of bodies which thus originate, are remarkable as a class for a degree of complexity of constitution far exceeding that observed in any of the compounds yet described.’ Fownes' Chemistry, 3rd edit., London, 1850, p. 353. I quote this, as the first authority at hand, for a doctrine which is universally admitted by chemists, and which is indubitably true, so far as our experiments have at present extended.
815
‘As the organic world is characterized by the predominance, in quantity, of carbon, so the mineral or inorganic world is marked by a similar predominance of silicon.’ Turner's Chemistry, edited by Liebig and Gregory, vol. ii. p. 678, London, 1847.
816
I mean, of course, to apply this remark only to the globe we inhabit, and not to extra-terrestrial phenomena. Respecting the organization or non-organization of what exists out of this earth, we have no evidence, and can hardly expect to have any for centuries. Inferences have, indeed, been drawn from telescopic observations; and attempts are now being made, abroad, to determine, by a still more refined process, the physical composition of some of the heavenly bodies. But without venturing, in this note, to enter into such discussions, or even to state their purport, I may say, that the difficulty of verification will long prove an insuperable barrier to our knowledge of the truth or falsehood of any results which may be obtained.
817
Mr. Simon, in his thoughtful and suggestive Lectures, says, ‘We may describe Pathology to consist in the Science of Life under other conditions than those of ideal perfection.’ Simon's Lectures on Pathology, London, 1850, p. 14. This is by far the best description I have met with; though, as it involves a negative, it cannot be accepted as a definition. Indeed, the context shows that Mr. Simon does not suppose it to be one.
818
I formerly adopted the commonly received division of organic statics, and organic dynamics; the statics being anatomy, and the dynamics being physiology. But, I now think that our knowledge is not sufficiently advanced to make this so convenient as the division into physiological and pathological, or into normal and abnormal, provided we remember that in reality nothing is abnormal. The practically useful, but eminently unscientific, doctrine, that there can be alteration of function without alteration of structure, has effaced some of the most essential distinctions between anatomy and physiology, and especially between morbid anatomy and morbid physiology. Until those distinctions are recognized, the scientific conceptions of professional writers must be confused, however valuable their practical suggestions may be. While men are capable of believing that it is possible for variations of function to proceed from any cause except variations of structure, the philosophic importance of anatomy will be imperfectly appreciated, and its true relation to physiology will remain undefined. Inasmuch, however, as, with our actual resources, the most careful dissection is often unable to detect (in insanity, for instance) those changes of structure which produce changes of function, superficial thinkers are placed under a strong temptation to deny their invariable connexion; and while the microscope is so imperfect, and chemistry so backward, it is impossible that experiments should always convince them of their mistake. Hence, I believe that until our means of empirical research are greatly improved, all such investigations, notwithstanding their immense value in other respects, will tend to lead mere inductive minds into error, by making them rely too much on what they call the facts of the case, to the prejudice of the reason. This is what I mean by saying, that our knowledge is not sufficiently advanced to make it advisable to divide the sciences of organic bodies into physiological and anatomical. At present, and probably for some time yet, the humbler division into physiological and pathological, may be deemed safer, and more likely to produce solid results.
819
Hunter, as we shall presently see, did take an extraordinarily comprehensive view of pathology, including the whole of the organic world and even the aberrations of form in the inorganic.
820