The name of Richard Roberts stands preëminent at this period, between 1820 and 1825, as giving to the power-loom several perfecting touches in the means for letting off the warp the small amount necessary at each pick, the means for taking up the finished cloth, the means for shedding the warp for the passage of the shuttle, and the adaptation of the stop motions of his predecessors. These changes gave practical life to the machine, and overthrew the barrier that obstructed the advance of the textile industry. They were, however, only a few of the improvements added in perfecting the power-loom, such as the automatic temple to hold the cloth extended and prevent drawing of the weft, the shuttle-guard to prevent accidental jumping of the shuttle from the race, the perfect weft-stop to bring the loom to a stand on breakage or failure of the weft, the protector mechanism to obviate a “smash” when the shuttle failed to box, and the loose reed, all of which stand out in bold relief as evidences of the progressive tendencies of the age, and combined in about the year 1838, more than a half century after Cartwright’s first conception of the idea, to complete the practical power-loom. The loom had not reached a stage of mechanical perfection; much yet remained to be done, but the plain power-loom of this period was both a practical and financial success. By its immediate predecessor, the hand-loom, a good weaver and assistant could work from forty to fifty picks per minute, and weave plain cloth. By the power-loom of 1840, one weaver could “tend” two looms running from 100 to 120 picks per minute and produce the same cloth. Without passing through the various steps which culminated in the power-loom for plain cloth, now in use, and tracing the causes that led to perfection of details, the amazing advance from the ancient and 18th-century hand loom to the power-loom of 1840 and that of to-day may well be shown by comparing the machines themselves. Such was the simple form of the power-loom. One half of the warps were alternately raised and lowered for the shot of weft; but as a woven fabric is one in which the warp and weft are united by passing them over and under each other, the figure or pattern of the cloth will be varied as the threads are crossed in different combinations, and this will depend on the order of raising and lowering the warp threads, and the introduction of different characters and colors of weft. This brings up for review the most important parts of the loom structure—the shedding mechanism and shuttle-box motions—through whose agencies the most beautiful and complicated designs are produced. [Illustration: WEAVING. THE OLD WAY.] [Illustration: WEAVING. THE NEW WAY.]