118 BIBLIOGRAPHY OF NORTH AMERICAN GEOLOGY, [bull. 
Turnbull (J. M.). 
1. Geological sketch of the Bankhead [Alberta] coal field. 
Can. Mg. Rev., vol. 23, pp. 213-214, 4 pis., 1 fig., 1904. 
Describes the general geology, the occurrence of the coal beds of Cretace 
age, and the character and mining of the coal. 
Turner (H. W.). 
1. Native copper in greenstone from the Pacific coast. 
Eng. & Mg. Jour., vol. 77, p. 276, 1904. 
Discusses the occurrence and origin of native copper. 
2. Notes on contact-metainorphic deposits in the Sierra Nevada Moi 
tains. 
Am. Inst. Mg. Engrs., Trans., vol. 34, pp. 666-668, 1904. 
See no. 1217 of the Bibliography for 1903, U. S. Geol. Surv., Bull. no. 240. 
3. The geological features of the gold production of North Ameri 
fin discussion of paper of Waldemar Lindgren.] 
Am. Inst. Mg. Engrs., Trans., vol. 34, p. 921, 1904. 
A note in regard to the geologic position of gold ores in the vicinity of Silil 
Peak, Nevada. 
4. Observations on Mother Lode gold deposits, California. 
Am. Inst. Mg. Engrs., Trans., vol. 34, pp. 973-974, 1904. 
Sec no. 1218 of the Bibliography for L903, l T . S. Geol. Surv., Bull. no. 240J 
Tuttle (George \\\). 
1. Recent changes in the elevation of hind and sea in the vicinity 
New York City. 
Am. Jour. Sci.. 4th ser., vol. 17, pp. 333-346, 1904. 
Discusses detailed investigations upon tidal variation and their bearing u 
the question of the elevation or subsidence of the land. 
Tyrrell (J. Burr). 
1. Report on explorations in the northeastern portion of the distill 
of Saskatchewan and adjacent parts of the district of Keewarfi 
Can. Geol. Soc, Ann. Kept., new ser., vol. 13, 48 pp., 1 pi., and map, 1 
(Published separately, 1902.) 
Describes the occurrence and characters of Pleistocene deposits and Cam 
Silurian and pre-Cambrian rocks, includes a list of Glacial stria? and ol : 
vations on the geologic structure, igneous rocks, and minerals of the re: f 
examined. 
2. Crystosphenes or buried sheets of ice in the Tundra of north 
America. 
Jour. Geol., vol. 12, pp. 232-236, 1 fig., 1904. 
Describes the occurrence, character, and mode of formation of the masse 
ice for which the names crystosphene and crystocrene are proposed. 
