114 SCIENCE IN SHORT CHAPTERS. 



find them in a region which he himself has directly ex- 

 plored. 



Mr. Geikie's connection with the geological survey of 

 Scotland has afforded him special facilities for making good 

 use of Scottish typical material, and he has turned these 

 opportunities to such excellent account that no student 

 after reading " The Great Ice Age" will find fault with its 

 decided nationality. 



The leading feature the basis, in fact of this work de- 

 serves especial notice, as it gives it a peculiar and timely 

 value of its own. This feature is that the subject as com- 

 pared with its usual treatment by other leading writers is 

 turned round and presented, so to speak, bottom upwards. 

 De Saussure, Charpentier, Agassiz, Humboldt, Forbes, 

 Hopkins, Whewell, Stark, Tyndall, etc., have studied the 

 living glaciers, and upon the data thus obtained have iden- 

 tified the work of extinct glaciers. Chronologically speak- 

 ing, they have proceeded backwards, a method absolutely 

 necessary in the early stages of the inquiry, and which has 

 yielded admirable results. Geikie, in the work before us, 

 proceeds exactly in the opposite order. Availing himself 

 of the means of identifying glacial deposits which the re- 

 trogressive method affords, he plunges at once to the lowest 

 and oldest of these deposits, which he presents the most 

 prominently, and then works upwards and onwards to re- 

 cent glaciation. 



The best illustration I can offer of the timely advantage 

 of this reversed treatment is (with due apology for neces- 

 'sary egotism) to state my own case. In 1841, when the 

 "glacial hypothesis," as it was then called, was in its in- 

 fancy, Professor Jamieson, although very old and nearly at 

 the end of his career, took up the subject with great en- 

 thusiasm, and devoted to it a rather disproportionate num- 

 ber of lectures during his course on Natural History. Like 

 many of his pupils, I became infected by his enthusiasm, 

 and went from Edinburgh to Switzerland', where I had the 

 good fortune to find Agassiz and his merry men at the 

 "Hotel des Neufchatelois" two tents raised upon a mag- 

 nificent boulder floating on the upper part of the Aar gla- 

 gier. After a short but very active sojourn there I (l did," 



