The patent shelf clock was a surprise to the rivals of Terry, because this change in construction had produced an absolutely new and improved model,--an unheard-of thing in clock making. The conservatism before shown by the colonial makers had stunted the growth of clock improvements in many ways, hence Terry's new invention produced a sensation. The change was such as to allow the play of weights on each side and the whole length of the case. The placing of the pendulum, crown wheel, and verge in front of the wheels, and between the dial and the movement, was another space-saving device, as was also the changing of the dial wheels from the outside to the inside of the movement plates. The escapement was transferred by hanging the verge on a steel pin, instead of on a long, heavy shaft inside the plates. This allowed the clock to be fastened to the case in back, making the pendulum accessible by removing only the dial. Thus Terry fairly revolutionized small-clock making, by introducing a new form, more compact, more serviceable, and cheaper than any of the older makes. In 1807 Terry bought an old mill in Plymouth and fitted it up so as to make his clocks by machinery. About this time several Waterbury men associated themselves to supply Terry with the materials, if he would make the clocks. With this steady income from machine-made clocks, and the profits from extra sales, he made, in a very short time, what was then considered quite a fortune. In 1808 he started five hundred clocks at once,--an undertaking which was considered foolhardy. People argued that there weren't enough people in the colonies to buy so many clocks, but nevertheless the clocks sold rapidly. In 1810 Terry sold out to Seth Thomas and Silas Hoadley, two of his head workmen. The new company was a leader in colonial clock manufacturing for a number of years, until competition brought the prices of clocks down to five and ten dollars. All these years Terry had been experimenting, and in 1814 he introduced his pillar scroll top case. This upset the clock trade to such an extent that the old-fashioned hanging, wooden clocks, which hitherto had been the leading type, were forced out of existence. The shape of the scroll top case is rectangular, the case, with small feet and top, standing about twenty-five inches high. On the front edges of the case are pillars, twenty-one inches long, three quarters of an inch in diameter at the base, and three eighths at the top, having, as a rule, square bases. The dial, which takes up a half or more of the whole front, is eleven inches square, while below is a tablet about seven by eleven inches. The dial is not over-ornamental and has suitable spandrels in the corners. The scroll top is found plain as well as highly carved, but always the idea of the scroll is present.