Loc. cit., p. 767.

Stabilization of the bituminous coal industry, Extracts from the award and recommendations of the United States Bituminous Coal Commission, Government Printing Office, Washington, 1920.

Umpleby, Joseph B., Strategy of minerals—The position of the United States among the nations: D. Appleton and Co., New York, 1919, p. 286.

Now known as Economic Liaison Committee.

Military geology and topography, Herbert E. Gregory, Editor. Prepared and issued under the auspices of Division of Geology and Geography, National Research Council, Yale Univ. Press, New Haven, 1918.

Davis, W. M., Handbook of Northern France, Harvard Univ. Press, Cambridge, 1918.

Excellent texts on this subject may be found in Military Geology and Topography, Herbert E. Gregory, Editor, prepared and issued under the auspices of Division of Geology and Geography, National Research Council, Yale Univ. Press, New Haven, 1918, and Engineering Geology, by H. Ries and T. L. Watson, Wiley and Sons, New York, 2d ed., 1915.

Atwood, W. W., Relation of landslides and glacial deposits to reservoir sites in the San Juan mountains, Colorado: Bull. 685, U. S. Geol. Survey, 1918.

Chamberlin, T. C., and Salisbury, R. D., Geology, vol. 1, 1904, pp. 555-556.