BIBLIOGRAPHY OF NORTH AMERICAN GEOLOGY, 1906-1907. 37 
Burchard, Ernest F. — Continued. 
350. Glass sand of the middle Mississippi basin. — U. S. Geol. Survey, Bull. 
no. 285, pp. 459-472, 1906. % 
Describes the glass-making industry of the region, the methods of preparation of the 
sand and its composition and physical properties, gla£s-sand deposits in use in Illinois 
and in Missouri, and undeveloped deposits in Missouri. Arkansas, Kansas, and Wisconsin. 
351. The Clinton or red ores of the Birmingham district, Alabama. — U. S. 
Geol. Survey, Bull. no. 315, pp. 130-151, 1907. 
352. The brown iron ores of the Russell ville district, Alabama. — U. S. Geol. 
Survey, Bull. no. 315, pp. 152-160, 1907. 
353. Portland cement materials near Dubuque, Iowa. — U. S. Geol. Survey, 
Bull. no. 315, pp. 225-231, 1907. 
354. (J lass-sand industry of Indiana, Kentucky, and Ohio. — U. S. Geol. Sur- 
vey, Bull. no. 315, pp. 361-376, 1907. 
355. Notes on various glass sands, mainly undeveloped. — U. S. Geol. Survey, 
Bull. no. 315, pp. 377-382. 1907. 
356. Southern red hematite as an Ingredient of metallic paint. — U. S. Geol. 
Survey, Bull. no. 315, pp. 430-434, 1907. 
Discusses the occurrence and geologic relations of hematite ores in Georgia and Ten- 
Description of the Lancaster and Mineral Point quadrangles. — See Grant and 
Burchard, no. 1021. 
The production in the United States in 1906 of bauxite and aluminum : of 
glass sand, sand, and gravel; and of fluorspar and cryolite, gypsum, and gypsum 
products and barytes. — See no. 2419. 
Burckhardt, Carlos. 
357. Geologie de la Sierra de Concepcion del Oro [Mexico]. — X e Congr. 
geol. intern., Guide des Excursions, Mexico, no. XXI V, 24 pp., geol. map, 1906. 
358. Geologie de la Sierra de Mazapil et Santa Rosa [Mexico]. — X e Congr. 
ggol. intern., Guide des Excursions, Mexico, no. XXVI, 40 pp., 17 pis. (inch 2 
geol. maps), 1906. 
359. La faune jurassique de Mazapil avec un appendice sur les fossiles 
du cretacique inferieur. — Mexico, Inst. Geol., Bol. no. 23, 216 pp., 43 pis., 1906. 
360. Sobre el descubrimiento del Trias marino en Zacatecas. — Soc. Geol. 
Mexicana, Bol., t. 2, pp. 43-45, 1906. 
Describes the occurrence of marine Triassic deposits in Zacatecas, Mexico. 
361. Sobre las rocas fosforiticas de las Sierras de Mazapil y Concepcion 
del Oro, Zacatecas. — Mexico, Inst. Geol., Parergones, t. 2, no. 2, pp. 63-67, 1 pi., 
1907. 
Describes the occurrence and composition of phosphatic rock in the State of Zacatecas, 
Mexico. 
362. Sur le climat de l'epoque jurassique. — Soc cient. "Antonio Alzate," 
Mem. y Rev., t. 25, no. 1, pp. 45-49, July, 1907. 
Burckhardt, Carlos, and Scalia, S. 
363. Geologie des environs de Zacatecas. — X e Congr. geol. intern.. Guide 
des Excursions, Mexico, no. XVI, 25 pp., 11 pis. (incl. geol. map and sections), 
1906. 
Borrows, A. G. 
364. Eldorado copper mine [Ontario]. — Canadian Min. Jour., vol. 28, no. 6 
(new ser., vol. 1, no. 3), p. 76, 1 tig., April 15, 1907. 
