Rising one means that the box is risen to the next shelf; rising two is risen to the next shelf but one, skipping one. This style of drop box can be driven at the speed of 170 picks per minute. Generally, a weaver attends to three of these looms, and an overlooker to from 50 to 60. For the check shirting trade looms to weave from 30-inch to 37-inch cloth are used.
OTHER MOTIONS.
An ingenious drop-box motion is manufactured by a Burnley firm, by which the weight of supporting the boxes, etc., is altogether removed from the pattern chain, which is consequently made of less cumbrous construction. Other firms claim decided advantages in respect of a greater skip than either Diggle’s or Wright Shaw’s motions—e.g., from the first to the sixth box. Skips of this extent are obtained principally by using several eccentric cams. One of these may lift a single box, a second may raise the boxes two spaces, and their effect in combination is a lift of three shuttles, and so on for greater effects.
CIRCULAR BOXES.
Circular boxes are seldom used for cotton goods. In this arrangement the shuttles are fixed in grooves formed in a block revolving at the slay end, and drawn round in either direction by hooks, one being placed at each side of the revolving barrel. The movement of the hooks is regulated by a pattern chain. The speed is about the same as a Wright Shaw motion.
GENERAL.
Any of these types of boxes may be used with the over-pick, and either with tappets, dobby, or jacquard shedding. Attempts have recently been made to apply the drop-box principle to a system of replenishing the loom with three or four cops of weft without a stoppage, by having them previously placed in the shelves and lowered on the breakage or running-off of the previous weft.
Coloured Spots.
Additional colour is introduced into cotton fabrics in spots and figures after the manner of embroidery, by using circle swivels or lappets. If a series of small spots in colour are required to be made, by using a drop-box loom with a jacquard or dobby the object is easily attained, but it necessitates the cutting away of much of the coloured yarn which has been picked across the cloth, and only a portion of which is required for the figure. Now, by using extra twist or weft, and only interweaving as much as is required for the figure alone, much waste can be prevented, and a firmer spot obtained. Take, for example, the spotted muslin so frequently used for window curtains; each figure only consists of a few inches of coarse yarn so loosely passed through the ground cloth, and apparently so entirely independent of the other spots, that a tyro can form no other explanation of their appearance there than that they have been sewn on.