A 100 machine is in rows of 4. A 200 (204) machine is in rows of 4 or 8. A 300 (304) " " " 6, 8 or 12. A 600 (612) " " " 12. An 800 (816) " " " 8 (usually 2/400’s). A 1200 (1224) " " " 12 (usually 2/600’s). The knives are placed on the slant so that their edge more readily catches the hook in lifting, while their under side presses the hooks out of the way when dropping. To place 408 hooks in one row is of course out of the question, and for compactness they are placed in 51 upright rows of 8’s; this advantage is more apparent in 1800 hook machines--the largest made. The machine is fixed to a gantree above the loom (_Frontispiece_), and in a single-action jacquard motion, such as has just been described, the knife is raised by a lever over the machine, worked by an upright rod driven by an eccentric or crank on the crank-shaft, so as to give one lift for every pick. The cylinder is suspended to a batten swinging from the top, and also worked by connection with the crank-shaft. The movement of the cylinder is to and fro; as it is moving from the needle board one corner is caught by a latch and the cylinder partially revolves, bringing another card to face the needles, against which it is then pressed. The batten type is preferable to the sliding cylinder, which is only used in sheds where the building renders the sliding cylinder more applicable. The frame work of the batten is more solid and strong. SINGLE AND DOUBLE LIFT. In the single-lift jacquard, the knife has to lift as often as the loom picks, and should a hook require to be raised several picks in succession, it has to be dropped between each pick and raised again. These defects are obliterated in the double-action jacquard. The machine, Fig. 64, has two hooks to each needle, they being connected at the bottom to one neck cord. Two sets of knives are used, one lifting when the loom picks from the right-hand side, the other when picking from the left, thus reducing the speed of the knife one-half; whilst as the hooks for one pick are being used, the other knife can be preparing for the next shed, and when lifting, keep up any leash several picks in succession, thus saving time, and so enabling the production to be increased. The Fig. 64 shows a double-action machine with a single cylinder, 400 hooks and swing batten, giving at least 50 picks per minute greater speed than a single lift with less vibration and strain. [Illustration: FIG. 63.] Fig. 63 shows the different shapes of jacquard needles, A being the ordinary one in plan, B another view of the same, C the double-action one, and D another style of single-action needle. [Illustration: FIG. 64. DOUBLE-ACTION JACQUARD, SINGLE CYLINDER.] The speed may still further be increased by having a double-action machine with double cylinders and two sets of needles and hooks (see Fig. 65).