Geology. 421 



II. Geology. 



1. Thirty -eighth Annual Report of the Director of the United 

 States Geological Survey; by George Otis Smith, Director. 

 Pp. 176, 2 pis., 1917.— The commanding position of the Geolog- 

 ical Survey among organizations devoted to advancing science 

 and developing the nation's resources is generally recognized; 

 but to appreciate the variety of its activities and its influence 

 on industry and in education, the annual reports should be read. 

 A general view of the Survey is gained by a list of its largest 

 items: 40,937 square miles of geologic survey, 32,245 square 

 miles of topographic surveys, 18,000,000 acres of lands classified, 

 1,197 stream-gaging stations maintained, and collection of sta- 

 tistics from 90,000 producers. The Survey staff numbered 934 

 and the number of published works 203. Geologic work 

 extended into every State, the Canal Zone, and the West Indies, 

 and the Survey cooperated with 25 States in geologic or paleon- 

 tologic studies. Assistance was also given to the Bureau of 

 Mines, Bureau of Standards, Office of Public Roads, the Forest 

 Service, the Indian Office, the War and Navy departments, the 

 Land Office, and several other institutions. Although much of 

 the regular geologic research has been carried on, the dominant 

 feature since the declaration of war has been the greater concen- 

 tration along economic lines and the scientific guidance of war 

 activities; the search for potash in desert basins, in ancient salt 

 and gypsum beds, in feldspar and sericite has been continued; 

 special investigations of sources of graphite, platinum, vana- 

 dium, antimony have been undertaken ; and the search for man- 

 ganese has been comprehensive. Much attention has been given 

 to coal and oil, and an interesting phase of the year's work is 

 the demonstration that 40,000,000,000 barrels of petroleum are 

 stored in the oil shales of Utah and Colorado — an astounding 

 figure when compared with 3,500,000,000 barrels, the total 

 amount yet produced within the United States. Special mili- 

 tary maps, descriptive publications, and reports on camp water 

 supplies have been prepared. The Survey has contributed 79 

 men to the Engineer Officers' Reserve Corps, 37 of whom were 

 in Prance on October 1, 1917. ri. e. g. 



2. Annual Report, 1915, of the Iowa Geological Survey, with 

 accompanying papers; George F. Kay, State Geologist. Vol. 

 26, 1917. Pp. vii, 456, 25 pis., 63 figs.— This annual report of 

 the Iowa Geological Survey contains three important papers on 

 glacial geology: The Iowan Drift, a review of the evidences of 

 the Iowan stage of glaciation, by William C. Alden and Morris 

 M. Leighton (pp. 49-212) ; Pleistocene Deposits between Manilla 

 and Coon Rapids, by George F. Kay (pp. 213-231) ; The Pleis- 

 tocene Geology of Northwestern Iowa, by J. Ernest Carman. 



