Geology. 239 



These are momentous questions to be considered and answered 

 in 58 pages, and' therefore the author does not waste time in pre- 

 liminaries, or in consideration of details. He believes that the 

 view, often advanced, that the features of the earth mentioned in 

 the title are caused by the contraction of a cold crust settling 

 down to fit a still hot, but cooling and contracting, nucleus, is 

 essentially wrong. He essays to prove that the crust is losing 

 beat faster than the interior, and that this interior, as compared 

 with the outer shell, is relatively stable. The latter, instead of 

 being under contractional stresses, is in a state of tension. The 

 relative movements of the outer surface, which give rise to earth 

 features, are ascribed to the action of water, which penetrating 

 downward to the heated zone below, returns in a hot condition, 

 warming the superincumbent masses and thus causing them to 

 expand. By this mechanism, in various ways, he endeavors 

 to show that the continents, volcanoes, and mountain ranges are 

 formed. 



While it is not probable that this brochure will be taken very 

 seriously by those who still hold by the nebular hypothesis of 

 the earth's origin, and will seem to followers of Chamberlin's 

 planetesimal hypothesis much like a charge upon windmills, it 

 may be still said that it is well and clearly written, and in places 

 contains suggestive ideas. l. v. p. 



3. Geological Survey of Canada; A. P. Low, Director. — 

 The following publications have been recently issued : 



Annual Report, New Series, Yolume XVI, for 1904 ; this 

 contains Reports A, B, C, CC, G, H and S and is accompanied 

 by a series of fourteen maps. Ottawa, 1906. It is stated that 

 this volume is the last to be published in this form, the plan 

 being to present in future each report as a separate publication. 



Summary Report for the calendar year 1906 ; pp. 206. Ottawa, 

 1906. 



The Falls of Niagara ; by J. W.W. Spencee, 1905-6. Pp. xxv, 

 490, with 43 plates and 30 figures. Ottawa, 1907. This volume 

 was noticed in an earlier number (vol. xxv, p. 455). 



Report on Gold Values in the Klondike high level Gravels ; 

 by R. G. McConnell. Pp. 34, with one plate and a geological 

 map. 



The Telkwa River and Vicinity, B. C. ; by W. W. Leach. 

 Pp. 27, with a geological map. Ottawa, 1908. 



Report on a portion of Northwestern Ontario, traversed by the 

 National Transcontinental Railway, between Lake Nipigon and 

 Sturgeon Lake ; by W. H. Collins. Pp. 23, with a geological 

 map. Ottawa, 1908. 



4. Geography and Geology of a Portion of Southwestern 

 Wyoming, with special Reference to Coal and Oil ; by A! C. 



Veatcil Prof. Papers, 56, U. S. Geol. Surv., pp. 178, 1907 

 (=1908). — This is a very important paper for statigraphers and 

 paleontologists, and, especially, for those interested in the discus- 

 sion as to whether the Upper Laramie is to be referred to the 

 Mesozoic or the Tertiary. The author shows that the Cretaceous 



