10 (rows binder) × 12 (needles for one row) = 120 needles to be used for binder.
Suppose we have four divisions in loom, hence, four harness-cords to one leash, for the figure section, or 492 × 4 = 1968 ends of warp used for figure. 1968 threads of figure warp require the same number of threads of ground warp, which must be divided by 120, the number of needles and hooks set apart for it in the machine, or--as each needle and hook carries one leash--120 leashes. 1968 ÷ 120 = 16 repeats; and 48 leashes, or four rows in the machine, must each have 17 harness-cords carrying 816 threads; and 72 leashes, or six rows in the machine, must each have 16 harness-cords carrying 1152 threads, = 1968.
VII. Tying-up a Jacquard Harness for Figuring Part of the Design with an Extra Warp, (part for Two Sections, part for Single).
This tie-up (the character of which is indicated in Fig. LVIII.) is used for textile fabrics having two distinct warps in part of the fabric, and a single warp in the remainder, for ground only. It will readily be seen in the drawing which explains this tie-up that one part of the fabric will have to contain more ends of warp per inch than the other, as the figuring is done with an extra warp upon the regular ground cloth. The number of ends of ground warp per inch will, as a general rule, be the same throughout the fabric. In Fig. LVIII., explaining this method of tying-up, the texture is twice as high in the figure stripe as in the ground part of the fabric. If 40 ends of warp per inch are used for the ground, 80 ends per inch must be used in the figured part, _B_ to _C_, _B´_ to _C´_.
A 200 machine is used in the illustration, divided as follows:
150 needles for the ground over the entire fabric, _A_ to _B´´_. 50 needles for the figure effects, _B_ to _C_, and _B´_ to _C´_.
The comber-board, therefore, must be arranged accordingly, (2-2/3 divisions in drawing executed). The depth of the comber-board is divided into two parts: _H_, _M_, _N_, _K_, the first; _M_, _N_, _O_, _P_, the second. The first contains leashes fastened to neck-cords attached to needles 151 to 200, or the figure part, _F_ and _F´_; the second contains leashes fastened to neck-cords attached to the needles 1 to 150, or the ground part for the entire fabric. In the drawing of lines showing the harness-cords of the Jacquard harness we have only indicated: