[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.