The huge mixing barrels containing the concoction of gun-cotton and wood alcohol are mechanically rotated to reduce the materials into a gelatinous liquid. In 1891, two barrels capable of holding 500 pounds of the film mixture were sufficient to meet all requirements for that year. As the demand grew and the industry expanded, the same building continued to be used by the Eastman Kodak Company, but now the mixing process, which ran day and night, could treat up to 200,000 pounds of material at one time with a battery of fifty barrels, each with eight times the capacity of the small barrels used in 1891.