On the Hydraulic Coal-Cutting Machine

Abstract

After stating the important aid which machinery had furnished in lessening manual labour, Mr. Embleton entered into a clear and practical explanation of the machine manufactured by Messrs. Carrett, Marshall, & Co., of Leeds, now in operation at the colliery of Messrs. Locke and Warrington, at Kippax. The paper was illustrated by diagrams and sections of the machinery, from which the author explained that the machine was actuated by water pressure, produced by an engine placed at the bottom of the shaft. The water is conveyed in malleable iron pipes to the machine, a distance of about 600 yards, the pressure employed varying from 150 to 300 Ibs. per square inch. The cylinder is 4½ inches in diameter, and 18 inches stroke, making 25 strokes per minute, and using in that time 40 gallons of water. The cutting bar is furnished with the three cutters, thus effecting, at one stroke, depth of three feet three inches. As much as 39 feet in length, on the face of the coal, has been cut in the above depth in an hour. At the conclusion of the paper, an animated discussion ensued between Mr. Philip Cooper, of the Holmes and Masbro’ Colliery; Mr. Jeffcock, senior; Mr. Warrington, and Mr. Embleton, when the latter explained that the cost per ton on the coal obtained, including interest of capital and all labour, varies from 3⅞ d . to 5½ d .; while hand-labour cost 8 d. per ton. The produce of slack is 8 per cent. by the machine, and ...