Mannheim Type Slide Rule with Leather Sleeve
Original Box & Booklets. Marketed as being made of Ivorite, this slide rule was manufactured by Keuffel & Esser Company, New York & New Jersey in the 1960s. All slide rules consist of three parts (the stock, the slide and the cursor or indicator) and have logarithmic scales that can be moved in relation to each other in order to do basic mathematical calculations. Slide rules were largely supplanted by electronic calculators in the 1980s.
Object ID: USGS-000653