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takes a long time on account of the currents in the rivers, and, consequently, competition with railroads is impossible. The Sabine was formerly navigated for three hundred miles from its mouth, while cotton boats capable of carrying a thousand bales made regular trips up the Trinity to Green's Landing, in the northwestern part of Anderson County. A small steam launch is also said to have once ascended this river as far as Dallas. The Brazos was navigated before the railroads came in up as far as the town of Washington, and boats are said to have gone up even to Marlin Falls, a distance of six hundred miles. The Colorado River has only been navigated in places. A small steamer carrying cord wood once plied a portion of the river in the neighborhood of Austin. A "raft" of drift timber at its outlet prevents the entrance of boats, and therefore prohibits any extensive shipping.
The smaller streams, such as the Neches and Angelina, are navigable for short distances above their mouths.
STRATIGRAPHY.
East Texas proper, i. e., the region east of the Brazos, is underlaid mostly by Tertiary strata, though to the northwest we come to Cretaceous beds, and on the coast we meet Post-Tertiary clays. The line separating the Tertiary and Cretaceous strata has not yet been accurately run, but points along it have been determined and are sufficient to allow a general line to be drawn. This line runs in a general southwest and northeast direction, crosses the Red River west of Texarkana; thence proceeding southwest it interects the Texas and Pacific Railroad near Elmo, nine miles west of Wills Point, and the Missouri, Kansas and Texas between Corsicana and the Trinity River; it crosses the Brazos in the northeast corner of Milam County; the Colorado ten miles below Austin. Between here and the Rio Grande the boundary line has not yet been run, but the first true Tertiary fossils found on that river, going down stream from Eagle Pass, are met in the northwest corner of Webb County and three miles below the Maverick County line, at a distance almost half way between Eagle Pass and Laredo. The uppermost part of the Cretaceous and the base of the Tertiary strata are both composed of soft clay and sand beds, which succumb readily to the weathering action of the atmosphere, and consequently the line of separation is often impossible to locate exactly. The uppermost beds of the Cretaceous in Texas and Arkansas are composed of sandy and "glauconiferous" strata, sometimes reaching a maximum thickness of three hundred feet. These have been termed the "glauconitic" division by Hill. They vary in composition from beds of pure siliceous sand to beds"
On the Rio Grande a steamer makes regular trips between Brownsville and Roma, and tradition says that government supplies were once taken up as high as Laredo.
American Journal of Science, Vol. XXXVIII, December, 1889.