System Wern ABC Circular Slide Rule


This plastic circular slide rule has a square white base with a transparent disc and pointer pivoted atop it. The outermost scale runs from 5 degrees to 90 degrees (going counterclockwise). Inside this, still on the base, is a scale from 0 degrees to 85 degrees. Immediately inside this is a scale for converting from degrees to radians. Other scales are for multiplication, division (showing decimal points in results), conversion of metric and standard units, squares, cubes (and square roots and cube roots), logarithms, sines, tangents (and arc sines and arc tangents), and percentages. A scale of equal parts 20 centimeters long, divided to millimeters, runs across the top of the base.

The device fits in a square black plastic envelope. Thie envelope also contains two sets of instructions on paper.

The slide rule is on the design of the American-born Swedish engineer Carl Wern and his younger brothers George and Lars Wern, also Swedes. They licensed rights to manufacture their slide rule to IWA Rechenschieberfabrik in Germany.

Date Made: ca 1966

Maker: IWA Rechenschieberfabrik

Location: Currently not on view

Place Made: Germany: Baden-W├╝rttemberg, Neckar

Subject: Mathematics


See more items in: Medicine and Science: Mathematics, Science & Mathematics, Slide Rules


Exhibition Location:

Credit Line: Gift of Carl R. Wern, George H. Wern, and Lars A. Wern

Data Source: National Museum of American History

Id Number: 2016.0133.01Accession Number: 2016.0133Catalog Number: 2016.0133.01

Object Name: slide rule with instructions

Physical Description: plastic (case, base, disc, runner material)metal (pivot material)paper (instructions material)Measurements: overall: .2 cm x 22.4 cm x 22.4 cm; 3/32 in x 8 13/16 in x 8 13/16 in


Record Id: nmah_1811360

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