[93] The banks of the river Montmorenci, from the natural steps downward to the St. Lawrence, are composed of a lime slate placed in horizontal strata from the depth of five to twenty-four inches, each connected by fibrous gypsum of a whitish colour. Heriot's Travels, p. 88. The island of Cape Breton abounds in sandstone, coal, and plaster. _Ibid._ 431.--JAMES. [94] Schoolcraft.--JAMES. [95] See his speech at the opening of the session of 1822.--JAMES. [96] Observations on the Geology of the United States, p. 57.--JAMES. [97] The following are descriptions of the rocks that alternate with each other as they occur, in connection with the coal-beds at Pittsburgh; commencing with the uppermost and proceeding in a regular gradation to the lowest, that we have had an opportunity of examining. No. 1. A loose-grained argillaceous sandstone, composed of minute grains of quartz and decomposed felspar, united by an argillaceous cement. Its colour is yellowish gray; fracture uneven; stratifications imperfect. It contains no organic remains; depth of the bed near four feet. No. 2. Bituminous shale; natural colour brownish black, that of the streak dark gray. Before the blow-pipe it decrepitates, burns with a bright flame, emits a bituminous odour, and soon becomes nearly white. Its structure is slaty; no animal or vegetable is contained in it, small veins of clay are dispersed irregularly between the layers. Depth of the strata ten feet. No. 3. A bed of bituminous coal; its colour is brownish black, cross fracture uneven, longitudinal slaty; fragments tabular, right angled; lustre resinous; is semihard, sectile and very brittle. Vertical and horizontal beds of indurated clay, containing a small quantity of bitumen, occur in the coal. Depth of the bed from two to eight feet. No. 4. Bituminous shale possesses the same character as No. 2. Varies in depth. No. 5. Indurated clay; its colour is lead-gray; fracture, in situations where it has been subjected to the combined actions of moisture and the atmosphere, irregularly slatose; in others uneven. Depth of this bed seven feet. No. 6. Argillaceous chlorite slate, passing by regular gradations into argillaceous chlorite sandstone. Natural colour, yellowish green, that of the streak light gray; cross fracture uneven. Its powder is soft and slightly greasy to the touch; it contains no organic remains. The depth of this bed varies. No. 7. Compact limestone, intimately mixed with alumine; it contains small veins of calcareous spar dispersed throughout the mass. Veins of angular fragments of carbonate of lime, united by a calcareous and argillaceous cement, extend irregularly through the rock. The fracture, in some specimens, is compact and earthy, in others uneven.