Triangles

A few squares and triangles from the Mathematics collection in the Medicine and Science.

The triangles in the mathematics collections illustrate the products sold by leading American makers of drawing instruments, including Darling, Brown & Sharpe of Providence, R.I.; and Keuffel & Esser of New York City. An American inventor, LeRoy J. Leishman, devised the Arcascope triangle and combination instrument. The objects on this page also show a transition from triangles made from steel, wood, and rubber to triangles made from plastic. The change in materials in the early 20th century has created a problem for preserving these instruments, as celluloid-based plastics are chemically unstable. Several of these objects are deteriorating despite efforts to store them in a controlled environment.

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Safe-T Open Triangles, Group of 2

These two translucent orange plastic triangles have rounded corners, triangle cutouts in their interiors, and slots for drawing lines parallel to each edge.
Description
These two translucent orange plastic triangles have rounded corners, triangle cutouts in their interiors, and slots for drawing lines parallel to each edge. They are both marked: SAFE-T TRIANGLETM (/) PO BOX 692 LaGrange, IL 60525 (/) Shatter Resistant SAFE-T PLASTICTM VIEW-THRUTM. The 4-7/8" 30°-60°-90° triangle is also marked: 42053. On the long leg, it has a scale of inches, divided to 1/16" for two inches and to 1/10" for two inches and numbered by ones from 1 to 4. The short leg has a centimeter scale divided to millimeters and numbered by ones from 0 to 6.
The 3-1/2" 45°-45°-90° triangle is also marked: 42054. One leg has a scale of inches, divided to 1/16" and numbered by ones from 1 to 3. The other leg has a centimeter scale divided to millimeters and numbered by ones from 0 to 8. The triangles were made in 1997 or earlier. In a company catalog (1998.0033.04), these models were renumbered to 42063 and 42064, respectively, and priced at 55¢ each. The pair could be purchased as a set for $1.35. The slots on the examples in the catalog were relocated to the corners of the triangles, so that they were easier to use for drawing templates of angles and triangles. Also, the model numbers were removed from the triangles. The form depicted in the 1998 catalog was still marketed in 2013.
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.
References: SAFE-T Products, Inc., Innovative Safe Drawing and Measuring Instruments, about 1998; "About Us," Classroom Products Warehouse, http://www.classroomprdcts.com/.
Location
Currently not on view
date made
before 1998
maker
Safe-T Products, Inc.
ID Number
1998.0033.01
catalog number
1998.0033.01
accession number
1998.0033

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