This slide rule is a circular version of those used for over one hundred years for performing multiplication, division and square roots for many technical applications. It had scales for basic multiplication and trig. functions. The scales did not move or slide against each other, which is uncommon.
Slide rules were very common until the mid-1970s, when they were all but replaced by electronic calculators. They came in many configurations, including models that had scales specialized for a particular engineering specialty, including aerospace. Aircraft crews often preferred the circular style, as it could be more easily manipulated with one hand.
This rule was found in the collection, stored with miscellaneous aviation materials of a variety of origins.
Display Status
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Country of Origin
United States of America
Type
INSTRUMENTS-Computers, General Purpose
Dimensions
3-D: 10.2 × 10.2cm (4 × 4 in.)
Materials
Aluminum
Steel
Coating
Plastic
Inventory Number
A19890112000
Credit Line
Donor unknown
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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