New York, New York: Leonard Atwood, Builder of High & Low Pressure Steam Engines and Safety Hoisting Machinery, 1870s. Bifolium (10.25" by 8") with illustrated advertisement for Leonard Atwood, Builder of High & Low Pressure Steam Engines and Safety Hoisting Machinery on first leaf, company letterhead on second leaf with space for date and correspondence. The illustration depicts a freight elevator on the left, and a safety passenger elevator on the right. Includes short description of how the elevators work, along with some of their other products, such as Hoisting Engines for mines and docks. Fine.