System Wern ABC Circular Slide Rule
date: label: date made
content: ca 1966
name: label: maker
content: IWA Rechenschieberfabrik
notes: label: Description
content: 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.
label: Description
content: The device fits in a square black plastic envelope. Thie envelope also contains two sets of instructions on paper.
label: Description
content: 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.
label: Location
content: Currently not on view
place: label: place made
content: Germany: Baden-Württemberg, Neckar
topic: label: Subject
content: Mathematics
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Science & Mathematics
label: See more items in
content: Slide Rules
creditLine: label: Credit Line
content: Gift of Carl R. Wern, George H. Wern, and Lars A. Wern
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2016.0133.01
label: accession number
content: 2016.0133
label: catalog number
content: 2016.0133.01
objectType: label: Object Name
content: slide rule with instructions
physicalDescription: label: Physical Description
content: plastic (case, base, disc, runner material)
label: Physical Description
content: metal (pivot material)
label: Physical Description
content: paper (instructions material)
label: Measurements
content: overall: .2 cm x 22.4 cm x 22.4 cm; 3/32 in x 8 13/16 in x 8 13/16 in