| Summary |
The purpose of this thesis is to present an in-depth study of John A. B. Dahlgren's heavy guns, their development and adoption by the navy. When first placed on board ships in 1856, Dahlgren guns were considered to be among the world's most powerful ordnance. They remained in service nearly until the end of the nineteenth century, by which time they were obsolescent. Shell guns were adopted by the French and British navies early in the second quarter of the nineteenth century. At this time, naval officials considered them to be controversial and they served as auxiliaries to guns capable of firing solid shot. Prior to this time, ordnance design was based on tradition and experience. The second quarter of the nineteenth century witnessed the application of scientific methods and experimental procedures to both ordnance design and metal 1urgy. Dahlgren guns were characterized by their unusual "soda bottle" shape. Dahlgren chose this shape because he believed it resulted in a stronger, more powerful gun and a higher safety factor for a given weight of metal than more conventional designs. His guns had sufficient strength to fire solid shot as well as shells. Dahlgren's design, however, was a synthesis of existing ideas rather than a product of innovation. A more unique aspect of the guns was their metallurgy. The first Dahlgrens produced for shipboard use were cast by methods that had been in use for centuries. Many of these guns exploded when test fired. Dahlgren's solution to this problem did not involve changing the design; instead, he modified the casting Later, the larger caliber Dahlgrens were cast by a new technique developed by Thomas J. Rodman, an army ordnance expert. technique. Dahlgren believed that his IX- and Xl-inch guns should arm ships batteries entirely, supplanting other types of ordnance. He argued that a battery of a smaller number of heavy guns was superior to a battery of more numerous, lighter guns. Naval officials were willing to use the IX-inch gun in conjunction with other types of ordnance in ships batteries, but at first, adamantly opposed the Xl-inch gun because they believed that its sixteen thousand pound weight was excessive. The IX-inch gun received general approval in 1854, but the Xl-inch gun was not fully approved until Dahlgren demonstrated its feasibility for ship- board use in 1857. Dahlgren's system of ordnance was never accepted as a whole: his guns were rarely used to arm ships' batteries to the exclusion of other types of ordnance other than on board the Monitors. |
