70 Reviews — Dr. Croll's Life and Work. 



the exception of glacial phenomena) he never spent a single clay's 

 earnest study. 



It is not our purpose to offer any criticisms in the Geological 

 Magazine on the volume by Mr, Campbell Irons now before us, 

 although a short synopsis of its contents may not be altogether 

 out of place. 



The early days of the Perthshire youth are duly recorded ; and 

 from this we pass to notices of his literary and early scientific work. 

 As regards the latter, our author observes (p. 97) that " for many 

 years he [Croll] devoted his attention chiefly to the great problems 

 of theoretic geology, and in 1864 he began the brilliant series of 

 solutions which make his name illustrious in the history of this 

 science." An account of the early physical papers, 1861-4, is 

 given, and we learn that, about the latter date, Dr. Croll received 

 the congratulations of the late Sir Andrew Eamsay on his work. 

 He was now fairly launched in his career of scientific speculation, 

 and, as a consequence, entered into correspondence with Ramsay, • 

 Lyell, Herschel, Hooker, Charles Darwin, and other eminent men, 

 both geologists and physicists. A very considerable portion of the 

 volume is devoted to this cori'espondence in connection with the 

 several subjects taken up by Dr. Croll, all of which bore more 

 or less on the questions discussed in " Climate and Time," first 

 published in 1875. In the following year he was elected a Fellow 

 of the Eoyal Society. 



This intermingling of personal history with scientific correspon- 

 dence is continued down to the period when Dr. Croll found it 

 necessary, in 1881, to resign his appointment on the Geological 

 Survey of Scotland owing to ill-health, after having served for 

 thirteen years. The scientific correspondence is still maintained, 

 and the letters he received with reference to "Climate and Time," 

 " Climate and Cosmology," etc., are often very suggestive. 

 Amongst other things Dr. Croll tried his hand at " Stellar 

 Evolution," a pursuit which involved him in correspondence 

 with Winchell, G. H. Darwin, Alfred E. Wallace, and other 

 distinguished scientists. In 1889 he received a letter of thanks 

 from Dr. Nansen, to whom he had sent copies of some of his 

 works. 



The concluding chapters relate to the " Closing days " of 

 Dr. Croll's career, when he returned to speculations more or less 

 metaphysical. The " Philosophical Basis of Evolution " was his 

 last work, and this he was just able to see in print before he 

 died. Mr. Irons also reproduces obituary notices — by Lord Kelvin 

 as President of the Eoyal Society, by a writer in Nature, and by 

 Mr. J. Home, of the Geological Survey of Scotland, all of which 

 do justice to Dr. Croll's character and attainments. 



A considerable portion of Croll's work made its first appearance 

 in the Philosophical Magazine and in the Reader, but he also 

 contributed several articles and letters to the Geological Magazink, 

 more especially in the years immediately preceding the publication 

 of " Climate and Time." The substance of these articles was for 



