388 REVIEWS 



in Vol. II. The descriptive contributions of Blackwelder are an important 

 factor of the investigation and give evidence at once of fidelity and skill. The 

 systematic and philosophic treatment by Willis presents in lucid form the 

 larger deductions of the investigation, embracing at once the stratigraphic, the 

 physiographic, and the dynamic. Although the order selected for presenta- 

 tion in these volumes is the natural and logical one, some will find it service- 

 able to read the systematic summation and the salient conclusions of Vol. 

 II first and seek the details on which they are based afterward. 



The previous work, of Richthofen, Pumpelly, and others have given us 

 some familiarity with the stratigraphic series of central China, and have 

 thus taken the flavor of freshness from some of the important lines of this 

 research, but new features of critical interest have been brought forth by 

 this investigation, more, indeed, than could have been anticipated, and 

 some of these are distinct surprises. The analysis of the deformations by 

 physiographic, as well as stratigraphic methods, and the determination of 

 geological stages by the former method are among the most notable contri- 

 butions. These cannot be reviewed in detail here, nor would it be best if 

 practicable, since they can be appreciated at their full value only by reading 

 at length the elegant verbal and graphic expositions which they have re- 

 ceived at the hands of an artist at once with pen, pencil, and camera. 



Perhaps the most startling and, in many respects, the most significant of 

 the results of the investigation was the discovery, on the Yang-tsi-kiang, in 

 about the latitude of New Orleans, of a thick glacial deposit lying below the 

 trilobite horizon of the Lower Cambrian. This discovery, supported by 

 evidences of similar formations at approximately the same horizons, as it 

 would appear, in distant parts of the earth, added to Coleman's recent 

 determination of a still earlier glacial formation at the base of the Huronian 

 in North America, and supported by the general deductions from cosmo- 

 gonic and physical data that have recently been advanced, makes it clear 

 that a radical reversal of ancestral ideas as to atmospheric evolution and 

 early climatic history is upon us. 



The admirable topographic work of Sargent furnishes an excellent basis 

 for the stratigraphic mapping and the physiographic induction. 



T. C. C. 



Glaciers of the Canadian Rockies and Selkirks. By William Hit- 

 tell Sherzer. Smithsonian Institution, 1907. Quarto, pp. 135. 

 This elegant volume gives the results of a systematic examination of 

 the Victoria and Wenkchemna glaciers in Alberta and of the Yoho, Asulkan, 

 and Illecillewaet glaciers in British Columbia. The study embraced the 



