abstracts: geology and hydrology 473 



to consist of ancient igneous and metamorphic rocks, overlain on the 

 lower slopes by clays, shales, and gravels of early to late Tertiary age. 

 The valley lands are covered with sandy soils, chiefly derived from 

 alluvium. A chapter on pumping tests, by Herman Stabler, con- 

 tains tables of value in determining the proper size of pumps and 

 prime movers for specified lifts, and acreages to be irrigated. 



G. A. W. 



GEOLOGY AND UYDROhOGY.— Ground water in Reese River 

 Basin and adjacent parts of Humboldt River Basin, Nevada. Ger- 

 ald A. Waring. U. S. Geol. Survey Water-Supply Paper 425-D. 

 Pp- 35 (95-129), pis. 6, fig. I. 1918. 



Reese River drains a long, narrow basin in central Nevada, and flows 

 northward to Humboldt River near Battle Mountain. The region has 

 long been devoted to stock-raising, but there is possibility of increasing 

 the present areas of hay lands, irrigated by flood water, by developing 

 ground water for irrigation. There are well-developed alluvial fans 

 along the valley borders, and several playas (dry lakes), in the lower 

 parts of the valleys. A geologic map (PI. VIII), based on the work 

 of the Fortieth Parallel Survey, shows the mountains to consist of 

 ancient granitoid rocks and Tertiary lavas, with sedimentary rocks of 

 Paleozoic and Mesozoic ages. In the valleys there are Tertiary lake 

 deposits in addition to Quaternary lake and stream materials. 



G. A. W. 



HYDROLOGY.— SoM^/t^rw California floods of January, IQ16. H. D. 

 McGlashan and F. C. Ebert. U. S. Geol. Survey Water-Sup- 

 ply Paper 426, Pp. 80, pis. 17. 1918. 



The 1916 flood, especially in San Diego County, Calif., was probably 

 the maximum since 1862. For nearly a month San Diego was prac- 

 tically cut off from communication with the rest of the State, except 

 by steamer. 



The important feature of this report is the very complete record of 

 precipitation and run-off. Rainfall records, covering the flood period, 

 are given for 156 points well distributed throughout this limited area, 

 complete monthly records for San Diego, Los Angeles, and Santa 

 Barbara, and a discussion of the intensity and distribution of rainfall 

 in southern California. There are complete records of daily discharge 

 for nearly all of the important streams, and tables of crest discharges 

 and run-off summaries which give drainage areas, run-off per square 



