Tommies Militaria and Collectables
British A.M. Douglas Combined Protractor and Parallel Ruler – WWII Military Navigation Tool
British A.M. Douglas Combined Protractor and Parallel Ruler – WWII Military Navigation Tool
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Product Description
The British A.M. Douglas Combined Protractor and Parallel Ruler is a finely crafted World War II-era navigation instrument designed for use by military personnel in field operations. Developed by A.M. Douglas, a respected manufacturer of precision tools, this ingenious device combines two essential functions in one compact unit—streamlining the map reading and plotting process for officers and cartographers.
Manufactured from high-quality clear acrylic or durable celluloid, the tool features a full 360-degree protractor etched with degree markings for precise angle measurement, critical for determining bearings and plotting courses. Attached to this is a set of parallel arms, allowing users to transfer directional lines and angles across a map while maintaining consistent orientation. This innovative combination of tools significantly reduced the time needed for accurate triangulation and route planning, particularly under combat conditions.
Used extensively by British and Allied forces, the A.M. Douglas tool was especially valued in artillery units, reconnaissance missions, and naval operations, where rapid and reliable calculations could mean the difference between success and failure. Compact and lightweight, it was designed to fit easily into map cases or field gear, making it a practical asset in both European and Pacific theatres.
Today, the A.M. Douglas Combined Protractor and Parallel Ruler is a sought-after collector’s item and a testament to wartime ingenuity. It stands as a historical reminder of the precision, discipline, and technical skill that underpinned Allied operational planning during the Second World War