illuminating unpurified gas. The gaseous mixture contains, in 100 volumes Coal-tar and ammoniacal liquor 15.6 Its ultimate elements, deducting the earthly matter, stand in the following proportion: Its colour is black, with a resinous and glistening lustre; structure somewhat slaty; fragments indeterminate angular; it is brittle; specific gravity, 1.38. Chemical Character. It burns with a bright flame; swells and agglutinates; its proximate constituents 54 35 - 11 One pound is equal to two cubic feet of illuminating gas. The gaseous mixture contains, in each 100 Its ultimate elements, deducting the earthy matter, will stand in the following proportion: Geological Situation. It occurs in beds of sandstone and indurated clay; clay slate and coal alternating with each other, with the exception of the roof and the floor of the coal being invariably a fine brick clay. No fossil plants had been as yet discovered in that coal. COARSE COAL. Houille grossière. (Brongniart.) Loc.-Port Arthur, Jerusalem Basin, V. D. L. Colour, steel grey, sometimes blackish; structure usually slaty; cross fracture coarse-grained; it is harder than the common slate coal, and heavier; specific gravity, 1.44. Chemical Character. It burns with difficulty, and slowly, unless kindled with wood, and emits little or no smoke; its flame is blue, and clear as that of anthracite, which, in its external character, it most resembles; it does not agglutinate, nor cake; its proximate constituents are One pound yields 14 cubic feet of illuminating gas, and some water strongly impregnated with hydrosulphurets, but no coke or tar. The gaseous mixture contains, in 100 volumes Its ultimate elements, deducting the earthy matter, stand in the following proportions: Loc. -Richmond, Jerusalem Basin, V. D. L. Colour, bluish steel grey; structure, foliated; fracture slaty, sometimes composed of brilliant laminæ, variously arranged; specific gravity, 1.75. Chemical Character. It burns with difficulty, yields little or no flame, and no bituminous odour: its proximate constituents are Charcoal 60.0 33.5 6.5 One pound gives 1032 cubic inches of very feebly illuminating gas. No coke or tar were obtained in the process. The gaseous mixture contains, in each 100 vo lumes Sulphuretted hydrogen Other inflammable gas Its ultimate elements, deducting the stand in the following proportion: — BITUMINOUS WOOD. (Jameson.) Lignite Xyloide. (Beudant.) Loc.-South Esk Valley, V. D. L. Its colour is clove-brown; structure ligneous; cross fracture conchoidal; lustre shining and resinous; the fragments have the external appearance of of compressed wood; specific gravity, 1.29. Chemical Character.-It burns easily, with a flame, without swelling or caking, and emits during combustion a sharp, fetid, and nauseous odour: its proximate constituents are Applied to the production of gas, one pound gives 3686 cubic inches of very impure and faintly illuminating gas. Every 100 parts of weight yield Pyroxylic acid 30.0 Its ultimate elements, deducting the earthy matter, stand in the following proportion: Carbon Hydrogen Oxygen Geological Situation. It occurs in alluvial land, in detached masses, which are sometimes compressed, forming beds, of which one part is carbonised, while the other remains in the state of wood. The valley of the tributaries of the Derwent, and that of the tributaries of the Tamar, abound in lignites of this description. SLATY GLANCE COAL. (Jameson.) Anthracite. (Brongniart.) Loc. -Recherche Bay, Jerusalem Basin, V. D. L. Colour, iron black; structure compact; fracture slaty, and the layers frangible; specific gravity, 1·46. Chemical Character. It burns with difficulty, yields little or no flame, and no bituminous odour: its proximate constituents are Charcoal Water 74.4 20.0 5.6 One pound gives 1100 cubic inches of very faintly illuminating gas: no tar or coke were detected in this coal. |