Fig. 35 shows how the raised hooks can be allowed to yield to the pressure of the needles. A, B, C, D are four hooks connected with two needles, 1 and 2. When the hook A is raised, if B, which raises the same warp--as will be seen by the connection of the tail cords with the harness at E--is not to be raised for the next shot, the needle 1 is pressed back by the card, and presses the hook B back from its knife as shown, the dotted line being its original position; the A hook, being connected with the same needle, must also be sprung back, but its head cannot get back, as it is held on the blade of the griffe, so that the wire would require to spring, if some escape were not made for it. The lower ends of the hooks are made V-shape in the grating, so that when raised, if pressed on by the needles, they can move forward as shown, the dotted line showing the original position of the hook A. When the hooks fall, they fill the slots in the grating, and are thus kept steady. G shows the tail cords as connected with the harness when both hooks are down; E shows them when one hook is up and the other down, and if the hook B was raised for the next shot, the tail cord on it would be tightening up as that on A would be falling, and the harness attached to them would be caught up a second time from the middle position, thus forming centre shedding with any portion of the harness that is raised several times in succession. With plain-texture cards the upper and lower portions of the shed would pass each other in the centre when the sheds are being reversed, all the even numbers of hooks being on one griffe, and all the odd numbers on the other.
The tail cord consists of two pieces of cotton cord, one fastened to each hook of a pair, then the two ends are together tied to the bunch of neck twines that are to hang from these hooks, as shown in Fig. 35, and at A, Fig. 36. When one hook is raised and the tail cord drawn up with it, the other portion of the tail cord, which is tied to the other hook, is slackened--as shown at A, Fig. 36--which causes a certain amount of friction on them. Also, when one hook of the pair is falling with the descending griffe, and the other hook rising, the pluck occasioned thereby on the cords, when the hooks are passing at the centre, has a tendency to wear and break them. Although this does not occur when the lingoes are of a moderate weight (18 to 25 per lb.), and when only a few neck twines are tied to each tail, yet when a large number of neck twines (say 20) are tied to each tail, with weighty lingoes, as may frequently be the case in weaving small patterns on woollen and worsted goods, the breakage of the tail cords is a common source of complaint, which not only gives the trouble of renewing them, but is liable to cause defects in the cloth, by the weaver not observing the breakage for some time, as one hook of the pair may be raising the neck twines--that is, in case of the tail cord to only one of the hooks breaking. To remedy this Messrs. Hancock, Rennie, and Hudson have this year (1890) introduced a patent link connection for joining the tail to the hooks, which only requires one cord, or double cord, to be used, instead of two as before. This is shown in Fig. 36 at B. When one hook is raised and the other down, the link is in the position shown at C. The old method is shown at A. When one hook is rising and the other falling, the partial turning of the link causes a loss of time equal to about a quarter of an inch of lift, and this eases the sudden pluck on the tail cord. When both hooks are down there is also a loss of a quarter of an inch in the lift when one hook begins to rise, caused by the turning of the link.