LAMARCK. 



165 



was an ardent advocate of the doctrine of uniform- 

 ity, as against the cataclysmal school. The main 

 principles are laid down in his Hydrogeologic, that 

 all the revolutions of the earth are extremely slow. 

 "For Nature," he says, "time is nothini;. It is 

 never a difficulty, she always has it at her disj)osal ; 

 and it is for her the means by which she has accom- 

 plished the greatest as well as the least of her 

 results. For all the evolution of the earth and of 

 living beings, Nature needs but three elements, — 

 ' space, time, and matter." Lamarck, unlike I)uffon, 

 did not touch Cosmogony ; but in his observations 

 upon Geology he learnt, the first of all lessons, that 

 in speculating upon the past we should not regard 

 it as a period of catastrophe, that the true method 

 of study is to observe the steady march of Nature 

 at the present time ; for its present operations suffice 

 to explain all the facts which we observe in all its 

 past. This led Lamarck to the extreme of denying 

 all catastrophes in Geology, and all leaps or sudden 

 transitions in living Nature. " Nature," he repeats, 

 " to perfect and to diversify animals requires merely 

 matter, space, and time." 



After this review of Lamarck's self-education, 

 intellectual equipment, and the influences of his 

 collateral studies, we come to his theory of the fac- 

 tors and nature of the Evolution of life, which were 

 first fully expressed in the Philosophic Zoologiquc, 

 and formulated later in the Histoire Naturcllc into 

 the four well-known propositfons : — 



