John Adolphus Bernard DahlgrenDied 12 Jul 1870 at age 60 (born 13 Nov 1809). American inventor of the smooth-bore cannon that was, from its shape, familiarly known as the “soda-water bottle.” The shape resulted from a design in which the thickness of metal was varied to match the differences in internal pressure occurring when the cannon was fired. The pressures were determined by boring holes in the walls of the gun and inserting as gauges such objects as pistons or musket balls. He developed the weapons primarily for use on small boats that patrolled the waterways. His iron smoothbores were adopted in 1850 (9-inch gun) and 1851 (11-inch gun). Although designed for use against wooden ships, the iron-clad Monitor class ships carried two of these guns in their turrets, which were replaced by the 15-inch Dahlgrens in 1862. |
