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The annexed engravmg is a perspective view of an improvement in Sawing Machinery, invented by Pearson Crosby, of Fredonia, N. Y., to whom a patent was granted for the same in April, 1851, but which has not yet been brought promi.nently before the public. The nature of the invention consists in making a circular saw with both faces convex, so that it will present a thin edge, where the teeth are cut, to avoid waste of the lumber, and red uce the resistance in cutting, and be gradually thicker towards the shaft to give the requisite thickness, to prevent " bucklin g " and insure a stearly motion at the periphery, when this is combined with a fixed gauge placed near the periphery of the saw on that side of the shaft opposite to where the lumber is presented to the teeth, so that the said gauge shall separate or spread the two parts of the planks, while they are being sawed, and thus prevent them from binding against the faces ot the saw. A is a neat strong saw frame j B is the driving belt communicating from the shalt of a steam engine or water wheel. It gives rotation to the shaft of the saw, C. D is the fixed bevelled gauge j B' is II belt running from a small pulley on the spindle of the sa w around a pulley on the shaft of the cone pulley, M. N is a belt running from the cone pulley to the one, L. 0 is a shipper for moving the said belt from the least diameter of M to its greatest, and vice versa, so as to vary the speed of the cone pulley, L. The shipper slides on a rod, P, and is moved when required by turning the screw, Q. The pulley, L, has a pinion on its spind le which gears into the wh eel, K, and moves it. On the shaft of said wh ael is a bevel pinion (unse en) whieh gears into the bevel w heel , J, and gives motion to the vertical shaft, I, on the upper end of which is a c og wheel, which m esh es into similar wheels on the base of the spindles of the back feed r ollers, F F. These rollers take in the plan ks at t he front, F' F'. There is a knuckle or loose collar at the neck of spindl e;I, to allow for the vibration of the fe ed rollers for planks having i rregularities. The fe ed roller can al so be set further from, o r nea??er to, one another, for thick and thin planks-there are slots in the bottom plate to allow the spindles of sairl rollers to be so moved, and the sct'ew, G, working in the side pl ate of the roll er frame, graduates the play of s aid rollers. D' is a trunk to carry off the saw-d ust. The screw, G, h as a spri ng on it of suffi cient tension to allow the rollers to play, and yet bend out the warpinl:s i n a plank, and insure its presentation in a proper manner to the edge of the saw, so that the part o f the plank slit will be of equal and uniform t hickn ess. The following is the claim of th is patent, viz. :- "Making the saw with both faces convex when combined with the guide, D." Thi s is a very excellent combi nation for s litti:!g planks by a circul ar saw, and must commend itselt to all conc er ned. More information may be obtained by letter addressed to the p aten t ee.
