Circular Slide Rule, Bearing Rate Computer, Felsenthal FNR-5
Social Media Share Tools
Object Details
- Felsenthal Instrument Co.
- Description
- Mathematical instruments have long been used to assist in aiming weapons. This circular slide rule is one such device. Made for use in antisubmarine warfare, it has two scales on the base, two scales on a concentric disc atop this, and a rotating pointer pivoted at the center. The base has scales for the target speed in knots and the range in yards. The rotating disc has scales for the bearing rate and angle on bow. The inner scales on both the base and the disc are in green.
- A mark on the lower edge of the base reads: SPECIAL DEVICES CENTER DEVICE 1-BA-2 (/) BEARING RATE COMPUTER. A mark on the disc reads: G. FELSENTHAL & SONS, INC. (/) PART NO. FNR-5.
- Felsenthal made bearing rate computers for the U.S. Navy from at least the 1950s until at least the year 2000. A tag received with the object indicates that this model was produced from 1952.
- Compare 1977.1141.33, 1977.1141.34, 1977.1141.35, and 1977.1141.36. This object is a smaller version of 1977.1141.34.
- Reference:
- U.S. Navy, Operations Specialist Volume I, NAVEDTRA 14308, 2000, p. 10-22 through 10-28. This volume was accessed online August 3, 2017.
- Location
- Currently not on view
- Credit Line
- Gift of Ben Wharton Rau and Margery Felsenthal Rau
- ID Number
- 1977.1141.33
- catalog number
- 336417
- accession number
- 1977.1141
- Object Name
- slide rule
- Physical Description
- plastic (overall material)
- Measurements
- overall: .2 cm x 11.7 cm x 11.5 cm; 3/32 in x 4 19/32 in x 4 17/32 in
- See more items in
- Medicine and Science: Mathematics
- Military
- Science & Mathematics
- Slide Rules
- National Museum of American History
- Subject
- Mathematics
- Record ID
- nmah_1213910
- Metadata Usage (text)
- CC0
- GUID (Link to Original Record)
- http://n2t.net/ark:/65665/ng49ca746aa-9141-704b-e053-15f76fa0b4fa
There are restrictions for re-using this image. For more information, visit the Smithsonian's Terms of Use page .
International media Interoperability Framework
IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more.