Reviews 



Preliminary Report on a Part of the Similkameen District, British 

 Columbia. By Charles Camsell. Geological Survey of 

 Canada. 

 This report covers the region about Princeton, including the Roche 

 River, Copper Mountain, Kennedy Mountain, and Bear Creek Mining 

 Camps, and the Tertiary coal basin of Princeton. Copper ores occur in 

 lodes with some gold and silver. Exploration of these deposits has been 

 considerable, but the development is limited. Placer mining has been 

 carried on in the district since i860, but is of little importance now. Plati- 

 num is found in the placers with the gold. E. R. L. 



Report on a Portion of Conrad and Whitehorse Mining Districts, 



Yukon. By D. D. Cairnes. Canada Department of Mines. 



Geological Survey Branch. 



The district lies along the western edge or the Central Yukon Plateau 



region just east of the Coast Range. The ores are chiefly of gold, occurring 



in quartz veins, sometimes with rich values in silver. The work on these 



veins was begun in 1905, and has since developed rapidly. Several seams 



of anthracite coal outcrop in the district, and should be of considerable 



value in the near future. E. R. L. 



Geology of the Taylorsville Region, California. By J. S. Diller. 

 U.S. Geological Survey Bulletin 353. 

 The topographic elements of the northern Sierras, to which the Taylors- 

 ville region belongs, are three fault blocks with prominent escarpments 

 to the east and long gentle slopes to valleys along the western borders. 

 Sedimentary rocks of Paleozoic, Mesozoic, and Cenozoic age, and igneous 

 rocks belonging to several periods are found in the region. The most 

 important periods of igneous activity are connected with the compression 

 and deformation of the rocks of the Sierra Nevada at the close of Jurassic, 

 and with the great uplifting and faulting at the close of the Cretaceous. No 

 great mines have been developed, but- forty or fifty smaller ones have 

 yielded a total value of $7,000,000, almost wholly in gold, with a little 

 silver and copper. E. R. L. 



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