Safe-T 45749 Compass
date: label: date made
content: 1998
name: label: maker
content: Safe-T Products, Inc.
notes: label: Description
content: This translucent light orange plastic instrument is wedge-shaped, with a rotating white plastic disc set inside the wide end of the wedge. One long edge of the wedge has a scale of four inches, divided to 16ths of an inch. The other edge has a scale of ten centimeters, divided to millimeters. These edges each have a row of 33 small circular holes. The holes are marked for the radius of various circles, from 1" to 5". To draw a large circle, a pencil is placed in the desired hole and the instrument is rotated while the user holds the disc.
label: Description
content: Two rows of four small holes are on the disc; one row is straight and one is bowed. The disc also has a small hole at its center. To draw a small circle of up to 1-5/8" diameter, a pencil is placed in the desired hole and used to rotate the disc, while the wedge is held in place. Five larger circles are around the edge of the disc. The wedge is marked: SAFE-T (/) COMPASS® (/) LaGrange, IL 60535-0692 (/) #45761 Pat. #4,353,166. It is also marked: π = 3.1416 (/) A = πr<sup>2</sup> (/) C = πd.
label: Description
content: Instructions are on white cardboard received with the instrument. According to a company catalog (1998.0033.04), model number 45759 sold for $1.19 around 1998. The design of the disc is covered by a patent received by John S. Kettlestrings of Wheaton, Ill., in 1982.
label: Description
content: Safe-T Products, Inc., of La Grange, Ill., was established in 1992 and specialized in drawing instruments that were safe for children. In 2006, the company became a subsidiary of A. Daigger & Company and its name changed to Classroom Products Warehouse. Kettlestrings (b. about 1933) is an inventor, designer, and entrepreneur who was associated with Tool-Less Hanger Corporation of Everson, Wash., in 2011.
label: Description
content: References: <i>SAFE-T Products, Inc., Innovative Safe Drawing and Measuring Instruments</i>, about 1998; John S. Kettlestrings, "Toy-Like Instrument for Drawing Circles" (U.S. Patent 4,353,166 issued October 12, 1982); Company Overview of Safe-T Classroom Products, Inc.," <i>Bloomberg BusinessWeek</i>, http://investing.businessweek.com/research/stocks/private/snapshot.asp?privcapId=27794340; "About Us," <i>Classroom Products Warehouse</i>, http://www.classroomprdcts.com/.
label: Location
content: Currently not on view
place: label: place made
content: China
topic: label: Subject
content: Mathematics
label: Subject
content: Drawing Instruments
label: Subject
content: Education
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Science & Mathematics
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content: Dividers and Compasses
creditLine: label: Credit Line
content: Collected at the American Mathematical Society annual meeting, 8 January 1998
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1998.0033.03
label: catalog number
content: 1998.0033.03
label: accession number
content: 1998.0033
objectType: label: Object Name
content: compass
label: Object Name
content: compass, drawing
physicalDescription: label: Physical Description
content: paper (overall material)
label: Physical Description
content: plastic (overall material)
label: Measurements
content: overall: .4 cm x 5.2 cm x 16.7 cm; 5/32 in x 2 1/16 in x 6 9/16 in