Sound Velocity Corrector, A Mathematical Chart

This device assists in calculations of changes in the range of a gun because of meteorological conditions, particularly wind speed and temperature. A rotating disc and pointer attached to the plastic base have the scales required to correct for wind speed. A scale toward the bottom of the base gives the temperature correction. Both of these corrections are in percentages of the range. Summing them gives the total meteorological correction as a percentage of the range. One then can use a range correction chart to find the actual range correction.
A mark on the front of the instrument reads: Signal Corps U. S. Army (/) SOUND VELOCITY CORRECTOR PT-62/TSS-1 (/) Order No. 3531-CEGSA-45 G. FELSENTHAL & SONS - CHICAGO.
The instrument was designed and made for the United States Army by G. Felsenthal & Sons of Chicago in 1945. It had Felsenthal designation FAS-2.
For a related range correction chart, see 1977.1141.43.
Accession file.
Currently not on view
Object Name
calculating disc & chart
date made
G. Felsenthal & Sons, Inc.
Physical Description
plastic (overall material)
overall: .1 cm x 26.5 cm x 20.2 cm; 1/32 in x 10 7/16 in x 7 15/16 in
place made
United States: Illinois, Chicago
ID Number
catalog number
accession number
Science & Mathematics
Mathematical Charts and Tables
See more items in
Medicine and Science: Mathematics
Mathematical Charts and Tables
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Ben Wharton Rau and Margery Felsenthal Rau

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