We may here remark, that the greatest art in the manu facture is in the preparation of the stuff, and in adapting the state of the tackle to the material employed. The stronger the rag, the sharper must be the tackle, else the stuff would become so wet, that is, it would retain the wa ter so much, that the vat-man could not, without much trouble, shake it out, and the paper would be very apt to shrink in size. This is the manner, however, to form a strong paper, and what is done in the preparing of bank note or even cartridge stuff. The best state of the tackle consists in the bars of the roller, and those of the plate, agreeing in every respect together; those in the washing engine should be thick and blunt, where rubbing only is necessary to free the material of the dirt ; and those of the beating engine are required, generally, to be sharper. But all this depends, as we have said above, on the state or quality of the material, and the thickness or thinness, S:c. of the paper to be made.
The chest is commonly a rectangular vessel, either of wood or stone ; but if it is of wood, it is lined with lead. The common size may contain 300 cubic feet, or three en ginefulls of stuff; but they vary very much. Round chests are, however, preferred, as they admit of agitators being placed in them, for the purpose of keeping the stuff from sinking. Agitators cannot be employed where there are angles in the chest, as the thick parts of the stuff would be driven into these angles, and rolls would be formed.
A small quantity of the stuff is then removed to the vat, by means of a pipe, and diluted with water. The vat is a large tub, about five feet square and four deep, with sides rather inclining outwards, made either of wood or stone. On one side of this the maker stands; along the vat is laid a board, with copper ribbands fastened lengthways on it, to make the mould glide along it ; this is called the bridge. To the left of the maker is a smaller board, one end of which is fastened in the bridge, the other rests on the side of the vat. In the bridge opposite to this. is fas tened a nearly upright piece of wood, called the ass. In the vat is a copper, communicating with a steam-pipe. to keep it hot ; there is also an agitator to keep the stuff of a uniform thickness.
We must now give a description of the moulds. A laid mould consists of a frame of wood neatly joined at the corners. Wooden bars run across it, about an inch and half distant from each other. Across these, and conse quently along the mould, the wires run ; from 15 to twenty cover an inch. A strong raised wire is laid along each of the cross-bars, to which the other wires are fasten ed ; this gives the laid paper its ribbed appearance.
The water-mark is formed by sewing a raised piece of wire in the form of letters, or any device that may be wished, on the wires of the mould, which makes the pa pet thinner in these places. The frame-work of a wove
mould is nearly the same ; but, instead of sewing on se parate wires, the frame is covered with fine wire-cloth, of from 48 to 64 wires in an inch. On both moulds, a deckel or moveable raised edging, is used ; this must fit very neatly, otherwise the edge of the paper will be rough.
There are always a pair of moulds laid on the bridge, and the woi kman putting on the deckel, brings the mould to a vertical position, dips it about half way up in the stuff before him, and bringing it to a horizontal position, covers the mould with the stuff, and shakes it gently. This operation is extremely difficult, for if the mould be not held perfectly level, one part of the sheet will be thicker than another. The sheet thus formed, has as yet no consistency, so that by turning the mould, and dipping the side covered with wire-cloth, in the vat, it is reduced again to pulp, if necessary ; he then pushes it along the small board to the left, and takes off the deckel ; here the coucher receives it, and places it resting on the ass, so as to get quit of some of the water ; the vatman puts the deckel on the other mould, and makes another sheet. The coucher stands to the left side of the vat, his face towards the maker ; on his right is a press in which the felts are ; the felts are porous pieces of flannel ; a plank three inches thick is before him on the ground ; on this he lays a cushion of felts, and on this another felt ; he then turns the mould and presses it on the felt, where the sheet re mains ; he returns the mould, and pushes it along the bridge ; by this time the maker has another sheet ready, which lie places on the ass, lays down another felt, and couches the sheet upon it They go on in this way, felts and paper alternately, till they have a heap of six or eight quires, which is about 15. or 18 inches high. They then draw it into the press, where a pressure of from 70 to 100 tons is applied, either by a lever or machinery. When it is sufficiently pressed, they strike off the check, and, from the elasticity of the flannel, the screw flies up with great rapidity. The felts are then drawn out on the other side, where a layer stands ; a board is put horizontally in the press, on which the layer places the felt ; he lifts up the sheet, which has now con siderable strength, and places it on another board to the other side ; places on the board another felt, whence the coucher takes them, and anew puts paper on them. Two men at the vat, and a boy laying, make about six or eight reams in ten hours. In the evening, the whole is put in to another press, and a moderate pressure exerted ; this is to get quit of the mark of the felt and of part of the water. Next clay it is all separated, which is called parting, and being again pressed, is carried into the loft. Fine papers are often twice parted and pressed, in order to give them a good surface.