BIBLIOGRAPHY OF SLATE. 143 
Zirkel (F.). Uber die mikroskopische Zusauimensetzung von Thonschiefern und 
Dachschiefern. 
Poggendorff's Annalen, vol. 144, 1871, p. 319. 
WORKS OF AN ECONOMIC CHARACTER, 
Bennett (H. D.) [U. 8. Vice-Consul at Nantes, France]. The slate quarries of 
Angers. 
U. S. Consular reports No. 24, p. 115, Jan.. 1891. 
Bottinger (C. ). Zusauimensetzung und Verhalten von Dachschiefer. 
Chem. Zeitung, vol. 19, p. 19, 1144, 1895. 
Bower (John). Slate quarries as an investment [England], 1865. 
Brunner (H.). Valuation of roofing slates. 
Abstract in English from Wochenschrift fur Pharm., 1889, in Jour. Soc. Chem. Indust. vol. 9, 
p. 393, London, Apr. 30, 1890. 
Campbell (J. L. & H. D. ). The Snowden slate quarries. 
The Virginias, vol. 5, p. 162, 163, 1884. 
Coons (Altha T.). Slate. 
Mineral Resources U. S., calendar year 1904, U. S. Geol. Survey, pp. 825-830. 
Crawford (J. J.). California slate and slate industry. 
Twelfth Report State mineralogist, California State Mining Bureau, 1894. (See also Eighth Rept.) 
Dale (T. Nelson). The slate industry at Slatington, Pa., and Martinsburg, W. Va. 
Bull. U. S. Geol. Survey, No. 213. Contributions to economic Geology ( 1902), pp. 361-364, 1902. 
Dale (T. Nelson). Note on Arkansas rooting slate. 
Bull. U. S. Geol. Survey, No. 225 Contributions to economic Geology, 1903-1904, pp. 414-4P'.. 
Dale (T. Nelson). Slate in Maine, Pennsylvania, Vermont (northern), Virginia, 
and West Virginia. 
Bull. U. S. Geol. Survey, No. 260. Contributions to economic Geology, 1904-1905, pp. 486-488. 
Dalies (D. C ). A treatise on slate and slate quarrying, scientific, practical, and 
.commercial, 3d ed., London, 1887, p. 186. 
Day (David T. ). Report on mineral industries in the United States at the Eleventh 
Census, 1890. 
Slate, distribution of quarries, production, labor, and wages, p. 662-665, 1892. 
Day (David T. ). Mineral resources of the United States, calendar year 1893, U. S. 
Geol. Survey. 
Slate in U. S., p. 549; in Great Britain, p. 551, 1894. 
Day (David T.). Slate. 
Mineral resources of the II. S., calendar year 1900, U. S. Geol. Survey, pp. 676-682. 
Mineral resources of the U. S., calendar year 1901, U. S. Geol. Survey, pp. 660-663. 
Mineral resources of the U. S., calendar year 1902, U. S. Geol. Survey, pp. 687-691. 
Mineral resources of the U. S-, calendar year 1903, U. S. Geol. Survey, pp. 776-780. 
Day (William C). The slate industry. 
Sixteenth Ann. Rept. U. S. Geol. Survey, pt. 4. Mineral resources I'. S. (1894), nonmetallic prod- 
ucts, pp. 473-482, 1895. 
Day (William C. ). Slate and the slate industry. 
Seventeenth Ann. Repf. U.S. Geol. Survey, pt. 3, continued. Mineral resources U. S. (1895), 
nonmetallic products, pp. 770-775, 1896. 
Day (William C). Slate. 
Eighteenth Ann. Rept. U. S. Geol. Survey, pt. 5, continued. Mineral resources U. S., L896, pp. 
992-1011. 
Nineteenth Ann. Rept. Geol. Survey, pt. 6, continued. Mineral resource- (J. S., 1897, pp. 248-264. 
Twentieth Ann. Rept. U. S. Geol. Survey, pt. 6, continued. Mineral resources U.S., 1898, pp. 
292-336. 
Twenty-first Ann. Rept. U. S. Geol. Survey, pt. 6, continued. Mineral resources I'. S., 1899, pp. 
344-352. 
Eckel (Edwin C. ). The slate deposits of California and Utah. 
Bull. U. S. Geol. Survey No. 225. Contributions to economic geology 1903, pp. 417-422. 
Bull. 275—06 11 
