1876.] GEOLOGY. 389 



His prophecy proved to be a true one with regard to any 

 continuation of any general work in the direction of Evolu- 

 tion, but his estimate of powers which could afterwards prove 

 capable of grappling with the ' Power of Movement in Plants,* 

 and with the work on ' Earthworms,' was certainly a low one. 



The year 1876, with which the present chapter begins, 

 brought with it a revival of geological work. He had been 

 astonished, as I hear from Professor Judd, and as appears in 

 his letters, to learn that his books on * Volcanic Islands,' 

 1844. and on 'South America,' 1846, were still consulted by 

 geologists, and it was a surprise to him that new editions 

 should be required. Both these works were originally pub- 

 lished by Messrs. Smith and Elder, and the new edition of 

 1876 was also brought out by them." This appeared in one 

 volume with the title ' Geological Observations on the Vol- 

 canic Islands, and Parts of South America visited during the 

 Voyage of H.M.S. Beagle.' He has explained in the preface 

 his reasons for leaving untouched the text of the original edi- 

 tions : " They relate to parts of the world which have been 

 so rarely visited by men of science, that I am not aware that 

 much could be corrected or added from observations subse- 

 quently made. Owing to the great progress which Geology 

 has made within recent times, my views on some few points 

 may be somewhat antiquated ; but I have thought it best to 

 leave them as they originally appeared." 



It may have been the revival of geological speculation, 

 due to the revision of his early books, that led to his recording 

 the observations of which some account is given in the fol- 

 lowing letter. Part of it has been published in Professor 

 James Geikie's * Prehistoric Europe,' chaps, vii. and ix.,* a 

 few verbal alterations having been made at my father's re- 

 quest in the passages quoted. Mr. Geikie lately wrote to me : 

 " The views suggested in his letter as to the origin of the 



* My father's suggestion is also noticed in Prof. Geikie's address on the 

 ' Ice Age in Europe and North America,' given at Edinburgh, Nov. 20, 



1884. 



