It is therefore a ‘compound mounting,’ and is known as a ‘presser’ or ‘pressure’ harness. For simplicity’s sake let us suppose the principle of the drawboy to be applied to shafts or healds, and take a simple figure, as [Fig. 1].
For it there are 5 parts, or it could be wrought with 5 leaves of heddles with a straight draught. [Fig. 2] shows the mounting; A A is the back mounting, which in this case is a shaft mounting, but would be a harness for a more extensive pattern. B, B are the pressure heddles or front mounting. These are 5 in number, as the ground or texture is taken as a 5-end satin or twill, C is the pulley box with the tail cords, D, D, passing over the pulleys, and tied to the wall or to the loom framing as at E. The knobs F hang over the weaver’s head, and are attached by cords H, passing through a hole board G, to the tail cords, D, D. There are heads on the cords H, and the holes in the hole board are made thus
; so that when the weaver pulls down a knob the bead can pass through the round hole, and the shaft or shafts of the back mounting attached to it will be raised, and can be kept in this position by drawing the cord into the notch or narrow part of the hole, which the bead will not pass through. Any number of shafts can be raised that are required to form the pattern, either by pulling down the knob for each shaft, or by having the knots corded to the shafts, so that each one will raise the proper number of shafts. Thus, in the figure, each knob is only tied to one of the tail cords; therefore a knob must be pulled down for each leaf of heddles to be raised, but each knob might be attached to any number of the tail cords according to the number of leaves of heddles it is required to raise, so that pulling down each knob in succession will complete the pattern. It might require too many knobs to do this, and then the former method would have to be adopted. When the weaver begins to work he draws the first figure shed with the back mounting by pulling down one or more of the knobs as is required; he then works over the ground treadles, b, b, till a change of pattern is required. Next he releases the drawn shed by pulling the cord out of the notch in the hole board; draws another shed, and works over the ground treadles as before. This gives the principle of how the draw loom works, but the principle of forming the texture with the back and front mountings combined will be fully explained under ‘Pressure Harness.’
[Fig. 3] gives the draw-loom harness; A, A is the carriage, or the rails that support the harness, which rests on the capes or side rails of the loom. Supported by the carriage is the pulley box P, which is a frame fitted with small pulleys, and must be sloped at such an angle as will allow the tail cords to sink when opening the sheds without obstructing the pulleys underneath them. The neck twines extend from the figures 1 to 8 to the knots above the hole board D D. The cords which connect the neck twines to the mails E, E are called sleepers, and those which connect the mails with the leads F, F are called hangers. The hole board is made of hardwood perforated with holes, which run from front to back in diagonal rows from right to left; it should be a little finer than the set of the reed, to allow for empty holes that are sometimes caused by the tie of the harness ending with broken rows of hooks in some or all of the repeats. In Scotland, for this reason, when the reed is set on 37 in., the cumber board, or hole board, is set on 36 in.
Fig. 3
B, B are the tail cords, attached to the neck of the harness at one end, and at the other end all of them are fastened to the tail stick M, by means of which they are secured to the roof of the house. There must be a tail cord for each part of the harness; here only eight are shown for the front row of the harness, and if there were eights rows of harness in the hole board, 64 tail cords would be required, and the complete harness would be made up of several repetitions of the 64 neck twines; four of these repetitions are here given for the first row of the hole board. Of course there might be 400 to 600 tail cords in a full mounting.