4 ADDRESS TO THE BRITISH ASSOCIATION, 1881. 



Powell ; Optics, by Brewster ; Mineralogy, by Whewell, 

 and so on. My best course will therefore be to take our 

 different Sections one by one, and endeavour to bring 

 before you a few of the principal results which have 

 been obtained in each department. 



The Biological Section is that with which I have 

 been most intimately associated, and with which it is, 

 perhaps, natural that I should begin. 



Fifty years ago it was the general opinion that 

 animals and plants came into existence just as we now 

 see them. We took pleasure in their beauty ; their 

 adaptation to their habits and mode of life in many 

 cases could not be overlooked or misunderstood. 

 Nevertheless, the book of Nature was like some richly 

 illuminated missal, written in an unknown tongue. 

 The graceful forms of the letters, the beauty of the 

 colouring, excited our wonder and admiration ; but of 

 the true meaning little was known to us ; indeed we 

 scarcely realised that there was any meaning to decipher. 

 Now glimpses of the truth are gradually revealing 

 themselves ; we perceive that there is a reason and in 

 many cases we know what that reason is for every 

 difference in form, in size, and in colour ; for every bone 

 and every feather, almost for every hair. Moreover, each 

 problem which is solved opens out vistas, as it were, of 

 others perhaps even more interesting. With this impor- 

 tant change the name of our illustrious countryman, 

 Darwin, is intimately associated, and the year 1859 will 

 always be memorable in science as having produced his 

 work on ' The Origin of Species.' In the previous year 

 he and Wallace had published short papers, in which 



