2018-08-302022-02-022018-08-302022-02-02https://hdl.handle.net/11124/172469Date of manufacture: 1930s.Monroe produced many models of mechanical calculators. The most famous and successful machine in the hand cranked series was the "Series L", such as this L-160, produced in the 1930s and continuing until the 1960s in several varieties and models. The later versions were electrically driven.born digitaldigital photographsComputersImage