In [Fig. CIX.], showing the lifter-boards, A is also used for the ground, and B for the figure; 26 rows of the machine are shown for explaining the tie-up for a texture known as “extra fine,” or equal to 832 heddles in the width of loom (one yard).
Jacquard machines for two-ply ingrain carpets are usually constructed with 34 rows, and 33-1/2 of these are used. 33-1/2 rows have 33-1/2 × 8, or 268 needles, which carry 1072 threads, the number actually used in what is termed a full “extra super.” Should only 30 of these be used, having 30 × 8, or 240 needles, and carrying 960 threads for warp, the carpet is termed “super;” and if 25 rows, with 25 × 8 = 200 needles are used, carrying 800 threads, the product is called “fine” ingrain, and represents about the lowest grade of these carpets. It frequently happens that we find slight variations in the number of threads used in the various grades of carpet named. The pattern may require such a change, or economy in production may induce the maker to use a smaller number; or, as is done in a few instances, a manufacturer may always make his “extra super” on 32 rows; but all such changes are done by a corresponding depreciation of the value of the fabric, as compared with a full “extra super” of 33-1/2 rows.
Fig. CXII.
Fig. CXIV. Fig. CXIII.
[Fig. CIX.], p. 74, illustrates the full 34 rows, and indicates 26 rows used for illustration of tie-up (4 rows empty on each side). In power-looms the raising of the different journals is generally accomplished by an arrangement of cams, but in hand-looms it is done by the lifter-boards.
In [Fig. CIX.] the four large holes on each side are made for this purpose, and the wires for raising the journals are shown by heavy lines in tie-up in [Fig. CVIII.], p. 73. [Fig. CXII.] represents the process of lifting the journals, as follows: