T. J. Rodman: Mid-19th century gun barrel research and design for the U.S. Army

Abstract The engineering contributions to heavy military ordnance of Captain (later Lieut.- General) Rodman are summarized from the seven technical reports he published during a 4-year period, 1856–1860, just before the American Civil War (see Fig. 1). His principal original contributions included, the internal or bore cooling of (hollow) cast guns, the introduction of the cutter gauge to measure gun powder pressure, studies of gun life endurance (fatigue) due to repeated firing and the development of prismatic gun powder, among many others. Rodman's name and work is little known among to-day's engineers and scientists (U.S. as well as British) though he may occasionally be recognized in connection with the development of the ‘soda bottle’ shaped gun, which is more usually attributed to Admiral J.H. Dahlgren [1] (see Fig. 2). The objective here is to identify Rodman's significant achievements and to illuminate the background to his contributions, to the development of the ‘soda bottle’ gun and his associated work in engineering science. An appended long Note 3 collects together some remarks about the books that were available for early 19th century engineering students at the Military Academy, West Point, in mechanics and strength of materials.