The U.S. Army used this wooden high-angle firing table when positioning 155 mm howitzer guns firing high-energy shells. The instrument has a white coating on both sides. A yellowed plastic indicator has wooden edges that are held together with brass rivets. The top edge of one side has scales for 100 yards and for range. This side also has three sets of scales for elevation, 10MSI, drift, and TF (target firing?). The sets of scales cover the use of M1 propellant with a muzzle velocity (MV) of 2,100; M1 propellant with MV 2,800; and M1917 propellant with MV 2,370. The left end is marked: 29105 (/) FT 155-S-2 C7 RULE No. 1. The right end is marked: HIGH ANGLE (/) GUN, 155MM. SHELL, H.E., M101 (/) M1 & M1A1 FUZE, M51.
The other side has scales for 100 yards and range along both long edges. The center of the rule has two sets of scales, both for elevation, fuze, drift, and fuze settings of M55 and M67 with M1 propellant. These sets of scales are marked with the letter N. The left end is marked: 29105 (/) FT 155-S-2 C7 RULE No 1. The right end is marked: GUN, 155 MM. SH. H.E., M101 (/) M1 & M1A1 FUZE, M51, M55, M67.
The Felsenthal Instrument Company of Chicago made these artillery rules for distribution by the bookstore at Fort Sill, Okla., from World War II through the Vietnam War. For other instruments used to position howitzers, see 1977.1141.25, 1977.1141.26, 1977.1141.27, and 2005.0271.02. For Felsenthal company history, see 1977.1141.01 and 1977.1141.02.
References: "Graphical Site Table," The Field Artillery Journal 35, no. 9 (September 1945): 548; accession file.
ID Number: 1977.1141.28
catalog number: 336412
accession number: 1977.1141
date made: ca 1960
Physical Description: wood (overall material)
Physical Description: plastic (overall material)
Physical Description: paper (overall material)
Physical Description: brass (overall material)
Measurements: overall: 1.1 cm x 29.4 cm x 6.8 cm; 7/16 in x 11 9/16 in x 2 11/16 in
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Credit Line: Gift of Ben Wharton Rau and Margery Felsenthal Rau
place made: United States: Oklahoma, Fort Sill