C-Thru Pocket Slide Rule
date: label: date made
content: 1943-1963
name: label: maker
content: C-Thru Ruler Company
notes: label: Description
content: This inexpensive five-inch white plastic rule has A and D scales on the front of the base; B, CI, and C scales on the front of the slide; and S, L, and T scales on the back of the base. The indicator is clear plastic. Underneath the slide is a table of equivalents and settings. The front of the slide also has a scale of six inches, divided to sixteenths of an inch, and a scale of 15.3 centimeters, divided to millimeters. The back of the slide has a table of decimal equivalents from 1/64 to 63/64. A brown imitation leather sheath is marked: POCKET SLIDE RULE MADE IN U.S.A. No. 27. For instructions, see 1988.0807.06. The postal code on the instructions indicates a date between 1943 and 1963. According to this sheet, the C-Thru Ruler Company of Hartford, Conn., made this rule. This firm, established in 1939 by teacher Jennie Zachs and acquired by Acme United Corporation in 2012, continues to make transparent drafting tools and drawing instruments.
label: Description
content: References: Brian Dowling, "Acme United Acquires Bloomfield's C-Thru Ruler," <i>Hartford Courant</i>, June 11, 2012; "About Us," <i>C-Thru Ruler Company</i>, http://www.cthruruler.com/.
label: Location
content: Currently not on view
place: label: place made
content: United States: Connecticut, Hartford
topic: label: Subject
content: Mathematics
label: Subject
content: Rule, Calculating
label: Subject
content: Education
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Science & Mathematics
label: See more items in
content: Slide Rules
creditLine: label: Credit Line
content: Gift of George A. Norton
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1988.0807.02
label: accession number
content: 1988.0807
label: catalog number
content: 1988.0807.02
objectType: label: Object Name
content: slide rule
physicalDescription: label: Physical Description
content: plastic (overall material)
label: Measurements
content: overall: .4 cm x 17 cm x 4.4 cm; 5/32 in x 6 11/16 in x 1 23/32 in