QUARRYING MACHINE. - For quarrying stone or excavating in rock, the machine illustrated in Fig. 3574 is employed. The engine is carried on a wrought-iron four-wheeled frame, running upon rails laid down over the site upon which the machine is to work. On each end of the main shaft is a flywheel A, carrying a crank-pin to which is attached the connecting-rod B, which with F is coupled to the frame by the pin C. The upper end of the lever B passes through a sliding plate attached to the crank-pin, and a reciprocating motion is imparted to the lever B by the revolution of the fly-wheel. The corresponding end of the lever F passes through a guide G bolted to the bottom of the vertical frame shown in the drawing. Motion is communicated from the upper to the lower lever by means of coupling-bars, between which rubber blocks D E are placed. The end of the lever F, passing through the guide G, gives motion to the group of five cutting tools I H These bars are of steel, placed side by side, and move in top and bottom clamps, as shown. The two bars I have chisel-ends set diagonally, while the others are square. The middle bar H is wider than the others, and extends to a somewhat lower level. By this arrangement, when the machine is advancing, the front pair and the middle chisel operate, and in traveling in opposite direction the rear cutters come into action. Within the top clamp there is a series of serrations, in which corresponding serrations in the chisel-bars fit, so as to prevent any movement.

Upon the main shaft is a worm J, which drives the worm-wheel K, the shaft of which extends diagonally toward the back of the engine and terminates in a bevel-wheel. On the rear axle are two other bevel-wheels, which can be moved to and fro by means of the lever M, so that either can be thrown into gear with the bevel-wheel first mentioned, and the machine is moved to and fro by this mechanism. Motion to the cutters is given by means of the lever F, which drives them up and down, the upper clamps serving as guides in the fixed standards.

The machines are made to cut channels at three different distances apart-4 ft. 6 in., 6 ft. 3 in., and 6 ft. 7 in. The standards can be set to any angle between a vertical position and one of 45°. The number of blows struck per minute is 150 on each side, and the rate of advance is 6 ft., the depth of cut varying from one-half inch to 1 inch, according to the nature of the material; and channels can be cut to a depth of 6 ft., but a depth of 13 ft. in sandstone has been cut.