American Mill began on the site of a saw and grist mill owned by Rufus West and Horace Vinton. In 1846, Phineas Talcott purchased the site, and in 1847 he and Nelson Kingsbury organized the American Mills Company and built a new mill as Rockville's textile factories were gaining recognition. The new mill, one of the first local enterprises to attract investors from outside the area, was a six-story structure 200 feet by 45 feet, with two stone stories below upper wood-framed stories and an attic finished with Greek Revival details and a bell tower. Timber from Allegheny County in western New York, supplied through Frederick Talcott's lumber mill, was brought to the school yard on School Street to be framed and raised before many onlookers. The mill chiefly produced cassimere, a high-quality wool fabric, using superior looms and other technological changes that required skilled workers. Many of these tradesmen came from foreign countries to Rockville, marking the beginning of the town's industrial age. The American Mill Company merged with the Hockanum Mills Company in 1918, survived difficult economic conditions in the 1920s and 1930s, but the rise of synthetic fabrics in the late 1940s brought the decline of the northern woolen industry, and the mill closed in 1951. In 1960, fire destroyed the old unoccupied wooden mill structure. The site later became home to Anocoil Corporation, which began operations there in 1958 and pioneered the first continuously anodized-lithographic printing plates, now used by most newspapers and printers worldwide.