II. Straight-Through Tie-up for Repeated Effects, in one Repeat of the Design.

This method of arranging the tying-up of the Jacquard harness is based upon the necessity for producing patterns having a larger number of warp-threads than the Jacquard used has needles. The principle to be observed is found in producing small effects which repeat themselves in the general design.

The number of cords for the leashes depends upon the frequency with which these repeats occur. Fabrics with stripe effects offer greater opportunities for reducing the number of hooks and needles than other designs. [Fig. XXXI.] illustrates such a design with its tie-up, using a 400 Jacquard machine with 8 rows. The pattern shows four distinct effects, as follows:

Fig. XXXI.

The next subject to consider is the different arrangement of repeated effects in one division. Commence at the left-hand side of the fabric sketch with effect A, which repeats only once in one pattern or one division. The illustration shows two divisions, and also that each hook of rows 1 to 16, inclusive, in the first division can be connected with each hook of rows 1 to 16, inclusive, in the second division, because these rows produce the same effect in the design, which repeats itself in these two places. This connection forms what is technically called a leash, and it will always be found that for every harness-cord a leash contains, there will be found a repeat in the design to correspond.

Effect B is repeated four times in the design, or in each division. By having two divisions for the illustration we find that to produce the necessary repeats in the design each hook of rows 17 to 21, inclusive, requires 8 harness-cords to each leash.

Effect C repeats twice in one pattern or one division. Having two divisions for the illustration, each hook of row 22, including row 34, requires 4 harness-cords to each leash.

Effect D repeats once in pattern, once in division. This will give a result similar to A, two divisions, row 35, including row 50, with two harness-cords to each leash. This tie-up illustrates the first row of every effect, and also the last leash, 400.

Adding the number of warp-threads in the full repeat of the pattern, we have:

Effect A = 128 threads.
Effect B = 40 threads.
Effect C = 104 threads.
Effect B = 40 threads.
Effect D = 128 threads.
Effect B = 40 threads.
Effect C = 104 threads.
Effect B = 40 threads.
----
624 threads.

Or, in other words, we are producing with a “straight-through tie-up for repeated effects” on a 400 Jacquard machine, a design, which would require a 600 machine on a common straight-through tie-up, including the two reserve rows, or 624 needles; in other words, a saving is made of 224 needles in one full repeat of the pattern.

In designing for looms tied up for similar styles, the repeats of effects must be kept in mind. The general style of every design may be changed, but the arrangement of the repeated effects cannot be altered without changing the entire Jacquard harness.