Conversion Factors, Reference Table for Engineers and Other Executives


This battered table, printed on heavy green paper, gives an alphabetical list of units of measure, conversion factors, and new units of measure. For example, for the unit of measure centimeters, the conversion factor is 0.3937. Multiplying a measurement in centimeters by the conversion factor gives a result in inches.

The table was distributed by Precision Equipment Company of Chicago, Illinois. The back of the table advertises the company’s shelving and safety steps. A sentence at the bottom of the chart reads: Reproduced with the Permission of Foxboro Co. and Exporters’ Digest.

The owner of the table inserted a row with the conversion factor of 1.151 for converting from nautical miles to statute miles.

Exporters’ Digest was published from 1927 through 1958. Foxboro Company was in business from 1912 through 1990. A surviving piece of trade literature suggests that the Precision Equipment Company was in business in the 1950s. Hence the rough date of 1950 assigned to the object.

Date Made: ca 1950

Location: Currently not on view

Place Made: United States: Illinois, Chicago

Subject: Mathematics

See more items in: Medicine and Science: Mathematics, Mathematical Charts and Tables, Science & Mathematics, Measuring & Mapping


Exhibition Location:

Credit Line: Gift of John White

Data Source: National Museum of American History

Id Number: 1981.0922.16Accession Number: 1981.0922Catalog Number: 1981.0922.16

Object Name: sheet

Physical Description: paper (overall material)Measurements: overall: .1 cm x 21 cm x 24.7 cm; 1/32 in x 8 9/32 in x 9 23/32 in


Record Id: nmah_904711

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