Neil A. Maclean Sulfur Dioxide Concentration Slide Rule
date: label: date made
content: 1938
name: label: maker
content: Neil A. Maclean Co.
notes: label: Description
content: This wooden rule has hand-lettered paper labels glued to it. The top of the base has a logarithmic scale for parts per million of sulfur dioxide. The slide has logarithmic scales for pounds of sulfur dioxide and gallons of liquid. By setting the number of gallons next to the desired number of parts per million, the user may find the weight of sulfur dioxide needed to add to the liquid. The lower part of the base is marked: Directions – Set gallons to treat opposite arrow – Read lbs sulfur Dioxide opposite P.P.M. desired. (/) Copyright 1938 Neil A. Maclean Co. 470 - 8th St. San Francisco. Cal.
label: Description
content: The back of the rule is stamped: DEC –5 1938. Over this is stamped: [S]URPLUS (/) DUPLICATE around the logo for the Library of Congress. The back is also marked: ©CI 1 pub. 23866. Neil A. Maclean Company (sometimes called NAMCO) was a California distributor of pesticides and agricultural supplies. It deposited this rule with the Library of Congress as part of its application for copyright (23866 is the copyright number for the device). The Library subsequently transferred the instrument to the Smithsonian. Another sample used to procure a copyright is 1983.3009.02.
label: Description
content: NAMCO was still on 8th Street in the 1940s, but according to its trademark records, it moved to Milpitas, Calif., by 1971. Van Waters & Rogers, a multinational pest control and chemical supplier now called Univar, acquired the company sometime between 1974 and 1975.
label: Description
content: Reference: Library of Congress Copyright Office, <i>Catalog of Copyright Entries: Part 4, Works of Art, Etc.</i>, n.s. 34 (1939): 163.
label: Location
content: Currently not on view
place: label: place made
content: United States: California, San Francisco
topic: label: Subject
content: Mathematics
label: Subject
content: Rule, Calculating
label: Subject
content: Chemical Industry
label: Subject
content: Manufacturing
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Science & Mathematics
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content: Slide Rules
creditLine: label: Credit Line
content: Transfer from Smithsonian Institution Libraries
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1983.3009.01
label: catalog number
content: 1983.3009.01
label: nonaccession number
content: 1983.3009
objectType: label: Object Name
content: calculating rule
label: Object Name
content: slide rule
physicalDescription: label: Physical Description
content: paper (part material)
label: Physical Description
content: wood (overall material)
label: Measurements
content: overall: .9 cm x 21.4 cm x 3 cm; 11/32 in x 8 7/16 in x 1 3/16 in