This is an engineering drawing of a horizontal steam engine of the type that was used at the Dahlonega and Charlotte Mints. The steam engine employed a flyball governor as a safety device. Source: Ferguson, Eugene S., ed. Early Engineering Reminiscences (1815-40) of George Escol Sellers. Washington, D. C.: Smithsonian Institution, 1965, page 67. Earlier from The Steam Engine, by Paul R. Hodge, (New York, 1840).