describe a circle or part of a circle round the centre of the spindle, and the teeth of the two wheels continue to take in each other. By this means the pulley Ag not only gives motion to, but serves likewise to tighten the revolving straps when drawn back by the swivel-screws Aq, Aq, Aq, Aq. Whenever it is necessary to shift the dickles nearer to or farther from each other, in order to vary the width of the sheet of paper, the wheels and pullies must likewise be shifted upon the spindles, and again fastened thereon (by the wedge or key passing through the socket of each) in such a position as to bring the pullies Ag exactly opposite their respective dickles to which they belong.

In order to make the velocity of the strap correspond with the velocity of the web, we make the pullies Ag, Ag, of the same diameter as the wet press cylinders, which give motion to the web, and cause them to make the same number of revolutions.

Ar is a bevel wheel, hung upon the spindle of the cylinder K, the teeth of which take into those of the pinions As, hung upon the spindle At, having another pinion of equal size at Au upon the opposite end thereof, the teeth of which take into the bevel wheel Av, having an equal number of teeth with the wheel A r, and is hung upon the dickle strap spindle An.

By inspecting the drawings and the relative disposition of the wheels, it will easily be seen that when the machine is in motion the straps will move in the proper direction. As it is a material point for the preservation of the web that the straps should move exactly with the same velocity as the web does, this must be ascertained by actual observation when the machine is in motion, and the diameter of the pullies must be corrected, if

necessary,

necessary; and this precaution becomes the more indispensible as the wet press cylinders are covered with flannel, cloth, or felting, which renders their diameters indeterminate. This lining or covering upon the cylinders prevents them from injuring the web, and produces a better effect upon the paper than the naked cylinders would do. To prevent the ruler bars yyy, &c. from being bent down by the weight of the dickles, crossbars, &c. resting upon them, we place two upright supports, Aw and Aw, under each of them, with joints and adjusting screws near the bottom at A, by which the web is brought to a horizontal position, that is to say, so much of it as extends from the roller C, near the vat, to the roller D, over which it passes, and receives another direction, the use of which we shall hereafter explain. The rollers marked Bb, &c. are for supporting the web, and keeping it level, having their spindles or pivots resting upon the brass bearings or carriages A y, affixed to the ruler-bars on each side of the machine, and made adjustable up and down, that the upper surfaces of the rollers may be brought level with each other. Az, &c. are a series of smaller rollers applied with the same intention as those last described, but having their bearings affixed to the inside of the under dickles. Ba and B a are two brass cylinders or rollers, including between them the two webs, in the same manner as it is done by the press cylinders J and K, and are supported by their pivots or spindles turning in the brass carriages at B6 and Bb, one of which is seen in the section, the upper end being a screw, by which it is fastened by the two nuts B d and Bd to the piece of iron Bc affixed to the carriages of the cylinders; the piece of iron B c, having a longitudinal mor

tise therein, through which the screw passes, and admits of its being moved backward and forward therein so as to alter the situation of the rollers B a and Ba, by bringing them nearer to or further from the press cylinders J and K, and by means of the screws Be they may be raised or lowered. The upper roller Ba is held down or pressed against the under one by means of weights suspended from the axis at each end, thereby giving a certain pressure to the paper, and expelling a portion of the water, previous to the harder pressure given by the cylinders J and K. Bf is a small roller resting upon the webs, and as near the upper cylinder J as may be, to allow of its revolving freely upon the webs without touching the cylinder. It is kept in its place by a piece at each end, as at Bg, and prevents the water which is expelled by the cylinders J and K from flowing back прои the paper, which it otherwise would do. And it is for this purpose likewise that we cause the under web in its approach to the cylinders J and K to descend, as from D, to J and K.

The direction in which the under web is conducted ́ on each side of the cylinders will be clearly understood by the sectional drawing. But note, that in this, as well as in every other place where the webs of wire or felting are mentioned, the same are to be supposed when the plan is inspected, because they could not be therein delineated without obscuring other parts.

Fig. 1 (Plate X.) in No. 2 of the drawings hereto annexed, is a section of the guide-wheels H H, by which we proceed more particularly to shew the method or manner by which the revolving webs and felting are kept extended laterally, and conducted in a proper direction. The line A A represents the web as extended across the machine

by

by the opposite guide wheels. B B are pieces of tape or leather sewed to each edge of the web A A. CC are two other thicker pieces of leather firmly sewed upon the edges of the former ones. DD a section of the ruler bars. GG the brass frame or carriage for the guide wheels, and is affixed to the ruler bar by the pin or key E E. The arbors or pins upon which the guidewheels turn are made fast in the carriages at FF. The edges of the wheels are turned or made in the shape represented in the section, and being placed at such a distance from each other as to admit of the pieces of leather B B passing freely between the opposed parts thereof, do apply themselves to, and fill the angles made by the pieces of leather C and B. From hence it will be understood that the action of the wheels against the pieces of leather C C will be sufficient to give the web any required tension, and to conduct it in the proper direction. But for the more convenient application of these guide wheels to other parts of the web and felting where the ruler bars are not used, we construct the frame or carriage differently; and instead of the forked end, as at II, we make them with a round pin, as at A A in the drawing No. 2, Fig. 2, wherein B is an iron socket, into which the pin is inserted and held in any required position by the screw C, and by making the piece of iron with the socket of an appropriate shape, the same may be conveniently applied to any part of the frame, as is done at AA and B B, &c. See the general drawing No. 1.

We shall now continue our description of the remaining parts of the machine delineated in the drawing No.1. At Bh, Bh, &c. are placed small rollers for the purpose of supporting the under part of the revolving under

web

web as it returns from E to C. Bi is a section of shallow trough which we place underneath the web, and of a width equal thereto, in order to receive the water which drains from the pulp after it falls upon the web at C, and to conduct it by a spout at any one side to any convenient receptacle, as at B k, from which it is again raised, and returned into the vat by means of the tubes or scoops Bl, placed round the axis B m, and revolving thereon, their extremities at the same time dipping into the receptacle at Bk, from whence the water is. to be raised, and is by them lifted and discharged at their other ends or orifices at B n, and conducted to the vat. As the construction of the tubes is sufficiently evident from the drawing, we need not enter into further particulars. We would only observe, that our reason for preferring the method above described to the more obvious one of a pump is, to prevent as much as possible the paper stuff or pulp which drains off in the water from being formed into small lumps or rolls by the mutual friction or rubbing of any parts of the apparatus. against each other; and our reason for returning the. water into the vat is, that we may prevent the waste or, loss of a considerable portion of the paper stuff, blue) size, &c. which would otherwise be sustained by its running to waste.

The effect produced by shaking the mould upon which the paper is commonly made is so well understood by every paper manufacturer, that we need not here either explain the intention with which it is done, or the necessity of doing it, but proceed to describe how we perform that operation by the machine. It will appear by considering the construction of the shaking bar, and its connection with the ruler bars and upright supports u u, that VOL. XIII.-SECOND SERIES. Hh

it