2. Controlling the thread during the downward motion of the needle by the combination of a friction-pad to prevent the slack above the cloth, with the eye on the needle-carrier for drawing back the thread, for the purposes and in the manner substantially as described. 3. Placing the bobbin from which the needle is supplied with thread on an adjustable arm attached to the frame, substantially as described, when this is combined with the carrying of the said thread through an eye or guide attached to and moving with the needle-carrier, as described, whereby any desired length of thread can be given for the formation of the loop without varying the range of motion of the needle, as described. The feeding described in the Singer patent was "by the friction surface of a wheel, whose periphery is formed with very fine grooves, the edges of which are slightly serrated, against which the cloth is pressed by a spring plate or pad." Although claimed by the inventor in the handwritten specifications, it was not allowed as original. The machines manufactured by the Singer company (fig. 29) were duplicates of the patent model. These machines were quite heavy and intended for manufacturing rather than for family use in the home. [Illustration: Figure 30.--I. M. SINGER & CO. NEW YORK SHOWROOM of the mid-1850s, as illustrated in _Frank Leslie's Illustrated Newspaper_, August 29, 1857; only manufacturing machines are shown in this illustration. (Smithsonian photo 48091-B.)] [Illustration: Figure 31.--HUNT AND WEBSTER'S SEWING-MACHINE MANUFACTORY exhibition and salesroom in Boston, as illustrated in _Ballou's Pictorial_, July 5, 1856; only manufacturing machines are shown. (Smithsonian photo 45771-A.)] Singer enjoyed demonstrating the machine and showed it to church and social groups and even at circuses; this personal association then encouraged him to improve its reliability and convenience. He developed a wooden packing case which doubled as a stand for the machine and a treadle to allow it to be operated by foot. Because of the dimensions of the packing case, Singer put the pivot of the treadle toward its center, about where the instep of the foot would rest. This produced the heel-and-toe action treadle, a familiar part of the sewing machine until its replacement by the electric motor. Both hands were freed to guide and arrange the cloth that was being stitched. Singer also added a flywheel to smooth out the treadle action and later an iron stand with a treadle wide enough for both feet. The treadle had been in use for two years before a rival pointed out that it might have been patented. To Singer's chagrin it was then too late for patent laws did not permit patenting a device that had been in public use.