154 BIBLIOGRAPHY OF NORTH AMERICAN GEOLOGY, 1906-1907. 
Purdy, Ross C. 
1972. [Review of] Clays, their occurrence, properties, and uses, by Heinrich 
Ries. — Econ. Geology, vol. 2, no. 5, pp. 513-518, 1907. 
Report of the committee on cooperation with federal and state geological 
surveys. — See Hice, R., and others, no. 1142. 
Purdy, Ross C, and DeWolf, Frank W. 
1973. Preliminary investigations of Illinois fire clays. — Illinois State Geol. 
Survey, Bull. no. 4, pp. 120-175, 1 pi., 3 figs., 1907. 
Purington, Chester W. 
1974. Vein mining in Alaska. — Min. and Sci. Press, vol. 92, p. 310, 1 fig., 
May 12, 1906. 
Includes notes on the occurrence of ore deposits in Alaska. 
1975. Do the geological relations of ore deposits justify the retention of the 
law of the apex? — Econ. Geology, vol. 1, no. 6, pp. 572-580, 4 figs., 1906. 
Purington, C. W. 
1976. The Vulture mine, Arizona. — Min. and Sci. Press, vol. 94, pp. 808-310, 
3 figs., March 9, 1907. 
Discusses the occurrence of gold in various geologic formations, and describes the 
geology and occurrence of gold ores in Mariposa County, Arizona. 
1977. Copper in serpentine. — Min. and Sci. Press, vol. 94, pp. 719-720, June 
8, 1907. 
Discusses an occurrence of copper in serpentine and its origin. 
Rafter, George W. 
Hydrology of the State of New York. — New York State Mus., 58th Ann. Rept., 
vol. 2 (Bull. 85, 11)05), pp. 1-902, 45 pis., 74 figs., 4 maps (2 in pocket). 1906.— 
See Rafter, 1, page 278 of Bulletin no. 301, U. S. Geol. Survey. 
Ralph, Edward W. 
1978. Mining conditions at Ely, Nevada. — Min. and Sci. Press, vol. 94, pp. 
120-121, 2 figs., January 26, 1907. 
Includes notes on the occurrence of the copper ores. 
Rand, J. C. 
1979. Some minerals occurring at Worcester, Mass. — Mineral Collector, vol. 
12, no. 11, pp. 165-166, January. 1006. 
Ransome, Frederick Leslie. 
1980. The probable cause of the San Francisco earthquake. — Nat. Geog. 
Mag., vol. 17, no. 5, pp. 280-296, 11 figs.. May, 1906; Min. and Sci. Press., vol. 
92, no. 24, pp. 396-397, 1906. 
Describes the geologic structure of the region surrounding San Francisco, Cal. 
1981. Geology of the Bisbee district, Arizona. — Eng. and Min. Jour., vol. 81, 
p. 1103, June 9, 1906. 
A short note calling attention to a misstatement regarding the author's work. 
1982. Review of " The copper deposits of the Clifton-Morenci district, 
Arizona," by Waldemar Lindgren. — Econ. Geology, vol. 1, no. 6, pp. 612-615, 
June, 1906. 
1983. The directions of movement and the nomenclature of faults. — Econ. 
Geology, vol. 1, no. S, pp. 777-787, 4 figs., 1906. 
1984. Preliminary account of Goldfield, Bullfrog, and other mining districts 
in southern Nevada.— IT. S. Geol. Survey, Bull. no. 303, pp. 7-83, 5 pis., 15 tigs., 
1907. 
Describes the general geology of these districts, the occurrence, character, origin, and 
relations of the ore deposits, yielding principally gold, and the mining developments. 
