220 Anniversary Meeting. [Nov. 30, 



philosophy and science conquering all obstacles and attaining to the 

 object of life-long devotion to scientific research and philosophical 

 speculation. Dependent wholly on his own work for his support, he 

 commenced earning a livelihood as a beginner in a merchant's office ; 

 and with his ability he might, no doubt, have earned promotion and 

 become a successful merchant.. But the superior attraction o 

 philosophy prevailed, and he wrote a book on the * The Philosophy of 

 Theism,' which was published in a large octavo volume, I believe 

 while he was still working in the merchant's office. After being one 

 out of about seventy unsuccessful candidates for the post of Under- 

 Keeper of the Hunterian Museum of the University of Glasgow, he 

 was appointed in 1859 to the post of Janitor of Anderson's College, 

 Glasgow. About this time the Geological Society of Glasgow was 

 founded, and became the centre of an active company of geologists, 

 who took up the study of the traces of the Glacial period, so striking 

 and abundant in the West of Scotland. Croll and his successful com- 

 petitor for the University post, John Young, both of them with 

 characteristic ardour, threw themselves into the work of geology. 

 Croll, according to his peculiar bent of mind, was drawn chiefly into 

 the more speculative lines of geological inquiry, and in 1864 pub- 

 lished his essay on ' The Physical Cause of the Changes of Climate 

 during the Glacial Epoch,' which deservedly gained the careful con- 

 sideration both of geologists and of astronomers. This speculation 

 undoubtedly presented a vera causa for some of the changes of climate 

 which have occurred in geological history, although we can scarcely 

 consider it adequate to be so powerful and exclusive a factor as 

 Croll endeavoured to make it. His vigorous dispute with Carpenter 

 regarding oceanic circulation rightly enforced attention to the 

 importance of wind as the prime mover of some of the great ocean 

 currents, but did not overthrow Carpenter's very important views 

 regarding the effects of heat, according to which differences of tem- 

 perature in the water itself in different regions and at different depths 

 have paramount efficacy in producing some of the great oceanic cir- 

 culations. After serving for eight years as Janitor in Anderson's 

 College, Glasgow, Croll was selected by Sir Archibald Geikie to take 

 charge of the maps and correspondence of the Geological Survey in 

 Edinburgh. But, according to rule, he must be examined, and the 

 Civil Service examiners plucked him in arithmetic and English com- 

 position. On the strong urgency of Sir Roderick Murchison (who 

 asked me, from my personal knowledge of Croll, to write a statement 

 of my opinion regarding his qualifications), the Civil Service Com- 

 missioners, with a wisely liberal relaxation of their rules, accepted 

 his great calculations regarding the eccentricity of the earth's orbit 

 and the precession of the equinoxes during the last ten million years 

 as sufficient evidence of his arithmetical capacity, and his book on 



