. The Americana : a universal reference library, comprising the arts and sciences, literature, history, biography, geography, commerce, etc. of the world . Fig- 5- enough to make another cut. Fig. 5 shows aJeffrey electric shearing machine in positionready to cut. It is rigidly supported by twomain columns at the balancing point of thestructure, to which the frame is tightly clamped,and the front end is steadied by two auxiliary. is 36 inches in height, 5, 6, or 7 feet in depth,and 4 inches in width. The average cuttingcapacity ranges from 50 to 100 feet per dayof 10 hours. The long-wall machi
. The Americana : a universal reference library, comprising the arts and sciences, literature, history, biography, geography, commerce, etc. of the world . Fig- 5- enough to make another cut. Fig. 5 shows aJeffrey electric shearing machine in positionready to cut. It is rigidly supported by twomain columns at the balancing point of thestructure, to which the frame is tightly clamped,and the front end is steadied by two auxiliary. is 36 inches in height, 5, 6, or 7 feet in depth,and 4 inches in width. The average cuttingcapacity ranges from 50 to 100 feet per dayof 10 hours. The long-wall machines are of two types,the cutter-bar machine illustrated by Fig. 6,and the cutter-wheel8 machine shown byFig. 7. A cutter-bar machine consists of a steelframe finished smooth on one of the long sidesso as to slide along the face of the coal. It issupported on the bottom on a steel shoe plate,and carrie? jpon the middle portion a powerfulelectric motor, the armature shaft of whichlies lengthwise of the machine and is gearedat one end to a sprocket which drives thecutter-chain* around a steel cutter-bar* ex-tending at right angles to the frame. Thesemachines are of the under-cutter type, andare capable of making cuts ranging from 38 to50 inches according to the length of the cutter-bar employed. The cutter-bar is carried on aswinging frame, and by means of a lever canbe tilted in its width up or down from thehorizontal posit
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectencyclo, bookyear1903
