Plotting Scale

Description
On one side this brass rule has an unnumbered scale of chords and architect's scales for making drawings at proportions of 1/5", 1/4", 1/3", 1/2", and 1" to the foot. The other side has 8" plotting scales with diagonal scales at each end. One plotting scale is divided to 1" and numbered by ones from 1 to 8, and the other is divided to 1/2" and numbered by ones from 1 to 16. A badly worn leather sleeve may not be original to the instrument. Compare to 1980.0676.01.
The Smithsonian's Division of Ethnology received this rule in 1951 and believed it to be of American manufacture.
Location
Currently not on view
date made
19th century
place made
United States
Physical Description
brass (overall material)
leather (overall material)
Measurements
overall: .1 cm x 15.4 cm x 3.1 cm; 1/32 in x 6 1/16 in x 1 7/32 in
ID Number
MA.388991.02
accession number
182022
catalog number
388991
Credit Line
Gift of Dr. and Mrs. Arthur M. Greenwood
subject
Mathematics
Drafting, Engineering
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Scale Rules
Data Source
National Museum of American History, Kenneth E. Behring Center

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