Metric Set Square
date: label: date made
content: ca 1800
notes: label: Description
content: This 6-3/8" brass rule unfolds to form a set square. The outer edge of one leg has a centimeter scale numbered by ones from 1 to 16. It is marked: N<sup>elle</sup> Mesure. The outer edge of the other leg has a scale for French inches (approximately 1-1/16") numbered by ones from 1 to 5. The first unit is divided into twelfths. The scale is marked: 6 Pouces. This leg has a pinhole for hanging a plumb bob and a rectangular hole with a rounded end (approximately 15/16" long) for viewing the plumb bob. The square has no maker's mark.
label: Description
content: For a brief history of squares, see MA.316929. Typically, the legs were marked with scales for measuring lengths. What is unusual about this square is that it has both a traditional French measure and a unit from the newly introduced metric system, which is denoted as a "nouvelle mesure," or "new measure." The metric system was created in France in the 1790s, after the French Revolution of 1789. This suggests a date of about 1800 for the instrument.
label: Description
content: Albert Haertlein (1895–1960), who collected this square, graduated with a bachelor's degree in civil engineering from the Massachusetts Institute of Technology in 1918. He served in the engineering corps of the U.S. Army during World War I and taught engineering at Harvard from 1919 until 1959. Haertlein was prominent in the American Society of Civil Engineers.
label: Description
content: References: "News From the Classes," <i>Technology Review</i> 21 (1919): 645; Albert Haertlein, Papers, HUG4444, Harvard University Archives, Cambridge, Mass.
label: Description
content: Entry 1985.0580.05.
label: Location
content: Currently not on view
place: label: place made
content: France
topic: label: Subject
content: Mathematics
label: Subject
content: Drawing Instruments
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Squares and Triangles
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content: Metric System
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content: Science & Mathematics
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content: Measuring & Mapping
creditLine: label: Credit Line
content: Gift of Mrs. Albert Haertlein
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1985.0580.01
label: accession number
content: 1985.0580
label: catalog number
content: 333926
objectType: label: Object Name
content: set square
physicalDescription: label: Physical Description
content: brass (overall material)
label: Measurements
content: overall, folded: 16.2 cm x 2 cm x .4 cm; 6 3/8 in x 25/32 in x 5/32 in