330 



SCIENTIFIC THOUGHT. 



same year which witnessed the appearance of the work 

 of Darwin was also that of the invention of Spectrum 

 Analysis, that great instrument by which astronomy, 

 doomed by the purely mathematical treatment to be- 

 come simply " une question d'analyse," was once more 

 enrolled among the natural sciences; the means being 

 supplied for that natural history of the heavens which is 

 now one of the most progressive and fascinating branches 

 of science. The reader who has realised from the fore- 

 going exposition how the genetic view of nature was 

 anticipated by earlier writers on cosmology, such as 

 Leibniz and Laplace, how it obtained in geology through 

 Hutton and Lyell, how it became dominant in embryo- 

 logy through von Baer, and how the morphological 

 treatment broke down through the recognition of the 

 variability of species and the impossibility of defining 

 clearly the landmarks of zoological and botanical classi- 

 fication, will readily understand the importance and 

 timeliness 1 of Darwin's work, which proposed to deal 



selection, no national or personal 

 jealousies obscure the issues which 

 were then at stake ; neither of the 

 two great naturalists has ever put 

 forward any complaint that the 

 other has not fairly and generously 

 dealt with his own merit. Since 

 the death of Darwin Mr Wallace 

 has written the well-known book 

 which, under the title of ' Darwin- 

 ism ' (London, 1889), gave to many 

 readers the first comprehensive 

 account of the celebrated theory 

 which is generously identified with 

 the sole name of only one of its 

 original propounders. 



1 Both propounders of the theory 

 of natural selection have in their 

 subsequent writings referred to 

 those who prepared the way be- 



fore them, and Mr Wallace has 

 taken special pains to explain why 

 a doctrine which was so well pre- 

 pared, and even anticipated, had 

 not been more distinctly accepted 

 before the appearance of the ' Origin 

 of Species' (" Darwinism," chap, i.) : 

 " Notwithstanding the vast know- 

 ledge and ingenious reasoning of 

 Lamarck, and the more general 

 exposition of the subject by the 

 author of the ' Vestiges of Creation,' 

 the first step had not been taken 

 towards a satisfactory explanation 

 of the derivation of any one species 

 from any other. Such eminent 

 naturalists as Geoffroy St Hilaire, 

 Dean Herbert, Professor Grant, 

 von Buch, and some others, had 

 expressed their belief that species 



