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The above engraving shows a saw mill which needs no end play in its saw arbor to ensure proper ranging of the saw, and accurate cutting of timber ; is automatic in its back and forward feed, being self-reversing and self-gigging back; is accurate and regular in its set of the log automatically, avoids the marring of the saw by the log or scratching of the log by the teeth of the saw, and, in fact, possesses all the requisites to a successful and profitable working of lumber, as extensive use of the same in the West has demonstrated. In the accompanying engraving, A represents the track or way on which the log carriage, G, travels back and forth alongside th,e circular saw by means of rack, F, and pinion, E. This carriage has two head blocks, G'-G', which are fed up laterally, or at right angles to the movement of the carriage, G, by means of a set lever, i, said lever coming in contact .with an inclined set bar, which raises it and Scauses it to turn the ratchet shaft, J, and thereby effect the lateral feed of the head blocks with unerring accuracy and uniformity. The saw arbor is set on a yoke, M. This yoke is adjustable by means of a pivot at a, and two set screws and oblique slots, m m, so as to set the saw oblique to the edge of the carriage or to cut toward the slab or log as de- sired. Thus setting the saw prevents the heating of it, and gives it its proper range for cutting accurately. The reversing of the carriage is effected by means of friction rollers and an adjustable roller, g. By shifting the roller, g, automatically by an eccentric on the shaft, n, which is turned slightly at each for- ward and backward motion of the carriage by reason of the carriage comingin contact with the trip, r. When the carriage strikes the trip, the friction roller, g, binds hard against either one or the other of the two rollers between which it lies, and thus the forward, reversing and gigging back motions of the log carriage are perfectly automatic. The motion to the saw and carriage are communicated by means of the belt, e, running over the pulleys, f f, as shown, the prime mover being the belt, B, which leads from the driving shaft of the engine. To start this mill continuously to work, it is simply necessary to throw tht lever, K, up to the position shown in the engraving, so as to bring trip, K', in position for being struck by log carriage. To stop the mill, the lever, K, must be depressed. The several operations of feeding, setting, reversing and gigging are all automatic, and after the mill is once started, it requires no attention further than to supply it with timber. We regard this as a most excellent saw mill, and know for a fact that it is extensively used in the West. It was patented April 6, 1858, by W. M. Ferry Jr., of Ferrysburg, Mich, who will furnish any further details.
