An Improved Method of Mining Coal or the like

9074. Kuhn, H. A. April 25. Drawings to Specification. Undercutting etc.; breaking-down appliances.-A process for mining coal and the like consists in making a number of cuts at the same time in the wall of material, and applying intermittent forces, during the cutting, to each portion of the partially severed material so as gradually to weaken and break down the material in lumps between pairs of incisions. The process may be carried out by means of the apparatus described in Specification No. 9094, A.D. 1908, [Abridgment Class Mining &c.], in which each of a series of parallel cutters is provided with wedges mounted thereon so as to apply forces alternately in opposite directions upon the material between the cutters.