Metric Set Square

Object Details

Description

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^elle 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.

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.

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.

References: "News From the Classes," Technology Review 21 (1919): 645; Albert Haertlein, Papers, HUG4444, Harvard University Archives, Cambridge, Mass.

Entry 1985.0580.05.

Location

Currently not on view

Credit Line

Gift of Mrs. Albert Haertlein

ca 1800

ID Number

1985.0580.01

accession number

1985.0580

catalog number

333926

Object Name

set square

Physical Description

brass (overall material)

Measurements

overall, folded: 16.2 cm x 2 cm x .4 cm; 6 3/8 in x 25/32 in x 5/32 in

place made

France

See more items in

Medicine and Science: Mathematics

Squares and Triangles

Metric System

Science & Mathematics

Measuring & Mapping

National Museum of American History

Subject

Mathematics

Drawing Instruments

Record ID

nmah_904465

Metadata Usage (text)

CC0

GUID (Link to Original Record)

https://n2t.net/ark:/65665/ng49ca746a7-7343-704b-e053-15f76fa0b4fa