Object Details
- Halpin Coairdinator Company
- Description
- This 7" white plastic rule has scales for statute miles and surface speed in miles per hour along both long edges, at proportions of 1:1,000,000 and 1:500,000. The interior of the rule is marked: AERONAUTICAL (/) INFORMATION (/) DATA SYSTEMS (/) HALPIN COAIRDINATOR (/) T.M. REG. U.S. PAT. OFF. (/) COPYRIGHT 1947 BY HALPIN COAIRDINATOR COMPANY WORLD RIGHTS RESERVED. A blue plastic propeller is riveted next to the companies' names. The rule is also marked in English and Spanish: READ SURFACE SPEED BY (/) MEASURING DISTANCE (/) COVERED IN 10 MINUTES (/) ELAPSED TIME (/) SEE REVERSE SIDE FOR SPEED CONVERSIONS.
- The back of the rule gives conversion factors for statute miles, nautical miles, and kilometers. This side also has conversion scales for feet and meters; liters, U.S. gallons, and imperial gallons; and kilometers, statute miles, and nautical miles. The center of the rule is marked: FOR CONVERSIONS ABOVE 100 ADD LIKE NUMBER OF CIPHERS TO EACH SCALE.
- The Halpin Coairdinator Company was founded in Florida in 1943. The firm and Aeronautical Information Data Systems jointly copyrighted a chart in 1947, but that object (38 X 27 cm) was much larger than this object. Halpin Coairdinator later copyrighted devices in Brazil as well as in the United States. The National Air & Space Museum owns a flight-route plan and a dead reckoning computer made by the company. A Thomas E. Halpin was director of training at Embry-Riddle School of Aviation in Miami, Fla., in 1941. Before 1928, he worked for Stout Aircraft and designed airplanes in Cincinnati, Ohio.
- References: Library of Congress, Catalog of Copyright Entries . . . Books . . . January–June 1947, 3rd ser., vol. 1 (Washington, D.C.: Government Printing Office, 1947), 115; Diário Oficial da União de 17 de Maio de 1954, p. 87, http://www.jusbrasil.com.br/diarios/2544433/dou-secao-1-17-05-1954-pg-87; Library of Congress, Catalog of Copyright Entries . . . Books and Pamphlets . . . January–June 1956, 3rd ser., vol. 10 (Washington, D.C.: Government Printing Office, 1957), 259; National Air & Space Museum, "Manufacturer: Halpin Coairdinator Co.," Collections, http://airandspace.si.edu/collections/cons.cfm?id=4932; Polk's Greater Miami City Directory (Jacksonville, Fla.: R. L. Polk & Co., 1941), 226; "Flamingo Production," Cincinnati Aviation Society & Museum, http://www.cahslunken.org/stories/FlamingoHist.htm.
- Location
- Currently not on view
- Credit Line
- Gift of Ben Wharton Rau and Margery Felsenthal Rau
- 1947
- ID Number
- 1977.1141.46
- catalog number
- 336444
- accession number
- 1977.1141
- Object Name
- scale rule
- rule
- Physical Description
- plastic (overall material)
- metal (overall material)
- Measurements
- overall: .1 cm x 17.9 cm x 4.1 cm; 1/32 in x 7 1/16 in x 1 5/8 in
- place made
- United States: Florida
- See more items in
- Medicine and Science: Mathematics
- Science & Mathematics
- Scale Rules
- National Museum of American History
- Subject
- Mathematics
- Navigation, Aeronautical
- Record ID
- nmah_1214762
- GUID (Link to Original Record)
- https://n2t.net/ark:/65665/ng49ca746aa-8f2c-704b-e053-15f76fa0b4fa
