The saw consists of an endless band of steel, either smooth or provided with teeth that are spaced according to the nature of the material to be worked.  It passes around the pulleys, P and P’, which are each encircled by a wide and stout band of rubber to cause the blade to adhere, and which are likewise provided with two flanges.  Of the latter, the upper one is cast in a piece with the pulley, and the lower one is formed of sections of a circle connected by screws.  The pulley, P, is fast, and carries along the saw; the other, P’, is loose, and its hub is provided with a bronze socket (Figs. 1 and 4).  It is through this second pulley that the blade is given the desired tension, and to this effect its axle is forged with a small disk adjusted in a frame and traversed by a screw, d’, which is maneuvered through a hand wheel.  The extremities of the crosspieces, D and D’, are provided with brass sockets through which the pieces slide up and down the columns, with slight friction, under the action of the vertical screws, g and g’, within the columns.

A rotary motion is communicated to the four screws simultaneously by the transmission arranged upon the frame.  To this effect, the pulley, P, which receives the motion and transmits it to the saw, has its axle, f, prolonged, and grooved throughout its length in order that it may always be carried along, whatever be the place it occupies, by the hollow shaft, F, which is provided at the upper extremity with a bevel wheel and two keys placed at the level of the bronze collars of its support, G. The slider, D, is cast in a piece with the pillow block that supports the shaft, f, and the bronze bushing of this pillow block is arranged to receive a shoulder and an annular projection, both forged with the shaft and designed to carry it, as well as the pulley, P, keyed to its extremity.  Now the latter, by its weight, exerts a pressure which determines a sensible friction upon the bushing through this shoulder and projection, and, in order to diminish the same, the bushing is continuously moistened with a solution of soap and water through the pipe, g, which runs from the reservoir, G’.

The saw is kept from deviating from its course by movable guides placed on the sliders, D and D’.  These guides, H and H’, each consist of a cast iron box fixed by a nut to the extremity of the arms, h and h’, and coupled by crosspieces, j and j’, which keep them apart and give the guides the necessary rigidity.

The shaft, m, mounted in pillow blocks fixed to the left extremity of the frame, receives motion from the motor through the pulley, p, at the side of which is mounted the loose pulley, p.  This motion is transmitted by the drum, M, and the pulley, L, to the shaft, l, at the other extremity.  This latter is provided with a pinion, l’, which, through the wheel, F’, gives motion to