ON THE GENETIC VIEW OF NATURE. 



363 



It is intelligible that these different lines in the 

 genetic view of nature the different trains of reason- 

 ing which, in the course of our century, have started 

 independently in astronomy, in geology, and in natural 52. 



J J> 5l7 ' Pateonto- 



history should, as they develop and expand, come into Io e ^^ ie 

 contact, and in the event either support or invalidate 

 each other. The former was the case when the geological 

 record, the discoveries of palaeontology, were brought in 

 to throw light on the history and development of species ; 

 the stories of nature, as written from the point of view 

 of the embryologist, the systematic zoologist and botanist, 

 and the paleontologist, seemed more and more to confirm 

 and support each other. The same cannot be said if we 

 write the history of our earth from the point of view of 

 the geological record on the one side and from that of 

 the purely physical data afforded by thermodynamics 

 on the other. Lord Kelvin has shown l that the untold 



We had only solar and stellar 

 chemistry ; we now have solar and 

 stellar physiology" (Presid. Address, 

 Brit. Assoc., 1871. See 'Popular 

 Lectures and Addresses,' vol. ii. p. 

 180). 



1 The literature of the subject 

 begins with Lord Kelvin's Address 

 to the Geological Society of Glas- 

 gow, February 27, 1868, which had 

 been preceded by a paper read be- 

 fore the Royal Society of Edinburgh 

 in 1865, briefly refuting the " Doc- 

 trine of Uniformity in Geology." 

 The address began with the words : 

 " A great reform in geological 

 speculation seems now to have be- 

 come necessary," and in the sequel 

 stated : " It is quite certain that a 

 great mistake has been made that 

 British popular geology at the pre- 

 sent time is in direct opposition 

 to the principles of natural philo- 



sophy." These papers are reprinted 

 in the 2nd vol. of ' Popular Lec- 

 tures and Addresses' (see pp. 10 

 and 44). The attack was taken 

 up by Huxley in his Address to 

 the Geological Society for 1869, 

 reprinted in 'Lay Sermons,' &c., 

 1891, p. 198. In a rejoinder to 

 this, delivered in the same year 

 at Glasgow (loc. cit., p. 73), Lord 

 Kelvin shows how the current 

 geology was in the habit of look- 

 ing upon geological time as " an 

 element to which we can set no 

 bounds in the past any more than 

 we know of its limits in the future " 

 (quoted from Page's ' Text-book '), 

 that Darwin's arguments themselves 

 involve an almost unlimited dura- 

 tion of the conditions admitting of 

 the operation of natural selection, 

 since, in his view, " in all probability 

 a far longer period than 300 million 



