CHAPTER IV
Babb. _Science_, Vol. XXI, p. 343. 1893. Clarke. _Data of Geo. Chemistry. Geol. Sur., U.S.A. Bull. 491._ —— _Smith. Misc. Collect._, Vol. LVI, No. 5. 1910. Dittmar. _Challenger_ Report, Vol. I, p. 203. 1884. Dole and Stabler. _Water Supply Papers. Geol. Sur., U.S.A._, Nos. 234 and 236. 1910. Geikie. _Trans. Geol. Soc., Glasgow_, p. 153. 1868.
Humphreys and Abbott. _Physics and Hydraulics of Mississippi River_, p. 148. 1876. Merrill. _Rocks, Rock weathering and Soils._ 1897. Murray. _Scot. Geog. Mag._, Vol. III, p. 65. 1887. —— _Scot. Geog. Mag._, Vol. IV, p. 38. 1888. Reade. _Chemical Denudation in Relation to Geological Time._ 1901. Russell. _River Development._ 1898. Schwarz. _Causal Geology._ 1910. Tylor. _Phil. Mag._, April, p. 258. 1853.