Chapter VI: Geology (3)

Among the economic products of the rocks are included mineral waters. The direct commercial value of such waters, not including their use for baths, etc., in the United States, is about $7,000,000 annually. The demand for these waters depends largely on the mineral substances they hold in solution, and which in many instances is in process of transference from one locality to another. Much might be written in this connection in illustration of the fact that the processes by which minerals, ores, etc., have been concentrated are still in progress.

LITERATURE

An extensive literature is available concerning the geology, minerals, ores, etc., of North America, but only a few of the more important publications can here be referred to. The numerous publications of the United States Geological Survey, the Geological Survey of Canada, and the Geological Survey of Mexico contain vast amounts of valuable information. Several of the States of the United States have independent surveys and have published numerous reports. Of journals containing articles of American geology, the more important are: _The Journal of Geology_, published at the University of Chicago; _The American Geologist_, published at Minneapolis, Minn.; _The American Journal of Science_, published at New Haven, Conn. The publications of a large number of learned societies in Canada and the United States should also be consulted.

The most useful bibliographies of North American geology are:

DARTON, N. H. _Catalogue and Index of Contributions to North
American Geology, 1732-1891._ Published as Bulletin No. 127 of
the United States Geological Survey, Washington, D. C., 1896.

DOWLING, D. B. _General Index to the Reports of Progress_ [of the
Geological Survey of Canada], _1863-1884_. Published by the
Canadian Geological Survey, Ottawa, Canada, 1900.

WARMAN, P. C. _Catalogue and Index of the Publications of the
United States Geological Survey, 1880 to 1901._ Published as
Bulletin No. 177 of the United States Geological Survey,
Washington, D. C., 1901.

WEEKS, F. B. _Bibliography of North American Geology,
Paleontology, Petrology, and Mineralogy for the Years 1892-1900,
Inclusive._ United States Geological Survey, Bulletins No. 188
and 189, Washington, D. C., 1902.

Of the numerous general treatises on the geology, the following will be found especially helpful to the student:

DANA, J. D. _Manual of Geology._ Fourth edition. American Book
Company, New York, 1895.

KEMP, J. F. _The Ore Deposits of the United States and Canada._
Scientific Publishing Company, New York, 1900.

LE CONTE, J. _Elements of Geology._ Fifth edition, revised and
partly rewritten by Prof. H. L. Fairchild. D. Appleton and
Company, New York, 1903.

MERRILL, G. P. _A Treatise on Rocks, Rock-Weathering, and Soils._
The Macmillan Company, New York, 1897.

SHALER, N. S. _Outlines of the Earth's History._ D. Appleton and
Company, New York, 1898.