Keuffel and Esser’s “‘Duplex’ Slide Rule” Advertisement
This advertisement for a Cox model duplex slide rule explained the new features of the rule, described how it worked, and noted how it differed from the Mannheim style rule. View the document »
Keuffel & Esser Co. announcement of Montreal branch house opening
After opening stores in Chicago (1891), St. Louis (1894), and San Francisco (1901), Keuffel and Esser expanded into Canada, where they opened a store in Montreal in 1908. Source: # 2010.025.0001, Hoboken Historical Museum. View the document »
Student’s Alphabets. A Selection of Useful Alphabets, No. 3571
This project is sponsored by the Transatlantic Program of the Government of the Federal Republic of Germany through funds of the European Recovery Program (ERP) of the Federal Ministry of Economics and Technology.