Dietzgen 1298-B Blackboard Ruler

This three-foot wooden rule was sold as part of a set of instruments for blackboard use. It is divided to 1/8" along one edge and numbered in red for feet and in black for inches. A horizontal handle in the center of the rule assists with positioning it against the blackboard, and a round hole at the right end is for hanging the instrument. The lower right corner is marked: DIETZGEN (/) MADE IN U.S.A. (/) 1298-B.
The Eugene Dietzgen Company of Chicago began numbering its blackboard drawing instruments individually by 1910, when it priced the four pieces at $1.25 each or $5.00 for the set. However, through at least 1938, the handle on the ruler was shaped like a knob, not as a horizontal bar. For related object, see 1999.0117.02.
References: Catalogue & Price List of Eugene Dietzgen Co., 7th ed. (Chicago, 1904), 151; Catalogue & Price List of Eugene Dietzgen Co., 9th ed. (Chicago, 1910–1911), 194; Catalogue & Price List of Eugene Dietzgen Co., 15th ed. (Chicago, 1938), 210.
Currently not on view
date made
ca 1950
Eugene Dietzgen Company
place made
United States: Illinois, Chicago
Physical Description
wood (overall material)
overall: 2 cm x 92.6 cm x 5.3 cm; 25/32 in x 36 15/32 in x 2 3/32 in
ID Number
catalog number
accession number
Credit Line
Gift of Montgomery College, Takoma Park, Md.
Rule, Measuring
Education, College
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Scale Rules
Data Source
National Museum of American History


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