Frederick Post Model 1795 Blackboard Compass

Description
In the years following the Civil War, American mathematics teachers began to use oversized compasses like this one to draw circles on a chalkboard. This example was sold by the Frederick Post Company of Chicago. It consists of two maple arms, each about sixteen inches (41 centimeters) long, which are held together by a wing nut at one end. At the other end are a rubber tip and a piece of chalk.
Makers often sold such instruments as part of a set that also included a straight edge, a protractor, a T square, and a triangle. After passage of the National Defense Education Act in 1958, such instruments could be purchased by secondary schools with subsidies from the federal government. This particular object was used in mathematics teaching at Montgomery College in Takoma Park, Maryland.
Blackboard dividers that are different from this instrument are advertised as model number 1781 in the Frederick Post Company's 1930 and 1936 catalogs. The instrument is not shown in the 1949–1950 catalog.
Location
Currently not on view
Object Name
compass, blackboard
compass, drawing
date made
ca 1950
maker
Frederick Post Company
Physical Description
wood (overall material)
chalk (overall material)
rubber (overall material)
metal (overall material)
Measurements
overall: 4 cm x 4 cm x 43.2 cm; 1 9/16 in x 1 9/16 in x 17 in
place made
United States: Illinois, Chicago
ID Number
1999.0117.01
catalog number
1999.0117.01
accession number
1999.0117
subject
Mathematics
Science & Mathematics
Education
School
Sputnik
Dividers and Compasses
See more items in
Medicine and Science: Mathematics
Sputnik
Dividers and Compasses
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of L. Thomas and Margaret G. Aldrich

Visitor Comments

Add a comment about this object

**Please read before submitting the form**

Have a comment or question about this object to share with the community? Please use the form below. Selected comments will appear on this page and may receive a museum response (but we can't promise). Please note that we generally cannot answer questions about the history, rarity, or value of your personal artifacts.

Have a question about anything else, or would you prefer a personal response? Please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Image CAPTCHA
Enter the characters shown in the image.