ON THE GENETIC VIEW OF NATURE. 



295 



which the recognisable strata of the earth's crust 

 with their fossil remains indicate as having occurred 

 in former ages. It was an attempt to " reconcile the 

 former and the present state of nature." 1 This was 

 to break with the idea of great and general convulsions, 

 to which the Continental school resorted in their ex- 

 planations, and it also meant upsetting the vague notions 

 which set a limit to the time 2 which should be allowed 

 for the operations of natural causes. It is possible to 

 admit that in both directions, in their uniformitarian 

 explanation and in their geological time -reckoning, the 

 new school frequently went too far, the indications 

 of actual catastrophes and paroxysmal convulsions being 

 to many observers quite unmistakable. On the other 

 side, the arguments based upon physical astronomy, 

 mechanics, and thermodynamics, which afford an inde- 

 pendent basis for geological time-reckoning, were not 

 yet elaborated, 3 or were deemed too crude 4 to be of 

 value; and for a good while geologists were permitted 



1 Lyell. vol. i. p. 114. 



2 Id. ibid., p. 241 : "When diffi- 

 culties arise in interpreting the 

 monuments of the past, I deem it 

 more consistent with philosophical 

 caution to refer them to our present 

 ignorance of all the existing agents, 

 or all their possible effects in an 

 indefinite lapse of time, than to 

 causes formerly in operation but 

 which have ceased to act." 



3 See Lyell, vol. i. p. 154, &c., 

 also vol. ii. p. 274 : "It has long 

 been a favourite conjecture that 

 the whole of our planet was origin- 

 ally in a state of igneous fusion, and 

 that the central parts still retain a 

 great portion of their primitive 

 heat. Some have imagined with 

 the late Sir W. Herschel that the 



elementary matter of the earth 

 may have been first in a gaseous 

 state, resembling those nebulas 

 which we behold in ! the heavens, 

 and which are of dimensions so 

 vast that some of them would fill 

 the orbits of the remotest planets 

 of our system. . . . Without 

 dwelling on such speculations 

 which can never have any direct 

 bearing on geology," &c. 



4 See Lyell, vol. i. p. 206, where 

 he refers to "astronomical causes 

 of fluctuations in climate," and to 

 the calculations of Sir J. Herschel 

 and the fact that " this matter is 

 still under discussion," and that 

 " MM. Fourier and Herschel have 

 arrived at very different opinions." 



