This page reviews some of the compass models used by the U.S. military in World War II. This is not an exhaustive list, but most of the common types are here.
Compass, Watch-Type was among the contents of the U.S. Army Air Force pilot's emergency kit which fits into the back pad of a parachute. In addition to the compass, it contains, among other things, concentrated food, emergency ration, a frying pan, knife, lighter, pistol and ammunition, gloves, and insecticide in a compact form. Photo above is a detail from a photo taken in the European Theater of Operations during World War II.
The Compass, Watch-Type was in common use in the U.S. military starting before World War I. From the outside, the compass has the appearance of a pocket watch. They were often made for the government by watch manufacturers such as Wittnauer and Waltham in addition to instrument makers such as Keuffel & Esser, S&W, Iszard Warren, or Taylor. The case was most often brass but nickel or chrome plated cases were also procured.
Most of these watches have "U.S." stamped on the case, but that is not universally true. It is also common to see "Eng. Dept." or similar indicating use by the Army Engineers. The manufacturer's name is also usually, but not always, stamped on the case.
In the early period of World War II, these pocket watch style compasses were still the most common. For example, the photo at the top of the page shows a pilot's emergency kit with a watch type compass included.
Compass, Prismatic, M-1938
Drawing of Prismatic Compass M1938 from FM 21-100 Soldier's Handbook, 11 December 1940. Shows compass open for measurement of azimuth at night my means of radiolite marker.
The M-1938 Compass, Prismatic has a similar design to the early Lensatic Compass but its cylindrical case stands higher and is not squared off with a ruler edge like the later lensatic compass models (see next photo below). The compass was used by officers and technical staff, and was not issued in large numbers to enlisted men. It was originally issued with a sturdy leather case that had a belt loop, not M-1910 equipment or cartridge belt hooks. Since it was relatively rare, it is an excellent item for World War II oriented collections. The photo to the left is from the book "Government Issue: US Army ETO Collector Guide," highly recommended as a photo-filled reference to World War II militaria.
The Lensatic Compass became the standard issue compass during World War II. As the successor to the M-1938 Prismatic Compass, the Lensatic Compass was simpler and cheaper to manufacture. In the U.S. military, it also replaced all the pocket watch type compasses before the end of World War II. For more information, see the Olive-Drab page on the Lensatic Compass. The photo to the right is a Lensatic Compass issued during WW II. The lettering says, "Corps of Engineers/U.S. Army" above the slot and "Manufactured By/Superior Magneto Corp./L.I. City N.Y..U.S.A." below.
Compass, Wrist, Liquid Filled
Airborne troops in World War II were issued a Bakelite plastic wrist compass with a brown leather adjustable band. This was the first plastic wrist compass, as further discussed on the Olive-Drab.com page on Wrist Compasses.
The M2 field artillery compass was in use during World War II. It is described on the Olive-Drab.com page for Compass, M2.
Other World War II Compasses
A number of other compasses were in used during World War II such as the "Compass, Prismatic M-1918" and the "U.S. Army Ordnance Model M-6" used by artillery units, as well as the non-magnetic "Sun Compass" used during the North African campaign in the desert. Manuals are still available for these compasses from some military booksellers, such as: TM 9-1595 Ordnance Maintenance. Prismatic Compass, M1918 (17 July 1941).
Another type of compass in widespread use was the Escape and Survival Compass. This was a small, concealable button compass that was inaccurate but better than nothing. A typical survival compass, packed with a map set, was brass with black enamel paint, about one-half inch in diameter.
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