US Navy 11-Inch Dahlgren Number 420 of USS Marion in St. Joseph, Michigan

Sep 7

US Navy 11-Inch Dahlgren Number 420 of USS Marion is displayed in St. Joseph, Michigan

US Navy 11-Inch Dahlgren Number 420 is displayed overlooking Lake Michigan at Lake Bluff Park in St. Joseph, Michigan. It was manufactured by Hinkley, Williams, and Company (formerly the Boston Locomotive Works) in 1864. As manufactured it weighed 15,890 pounds. Bureau of Ordnance records show that it was in storage until 1875 when it was mounted on the steam sloop USS Marion then building at Portsmouth Navy Yard (Kittery, Maine). In 1879 it was removed when Marion received an 8-Inch Rifle in its place.

USS Marion was very implausibly the “rebuilding” of a small sailing sloop-of-war first built in 1839. The resulting ship which was something like double the displacement of the original commissioned in 1875. The new Marion also had a steam engine and a more modern armament. To be fair to the Navy, this was probably a far more useful expenditure than repairing several rotting, hopelessly obsolete hulls.

11-Inch Dahlgren Number 420 was dedicated as a monument by the A.W. Chapman Post Number 21 of the Grand Army of the Republic on July 5th, 1897.

Number 420 was manufactured by Hinkley, Williams, and Company (formerly the Boston Locomotive Works) in 1864.

The 11-Inch Dahglren as a type: The 11-Inch Dahlgren, often referred to as “XI-Inch” in period sources, is probably most famous for its use in the turret of the USS Monitor. 11-Inch Dahglrens were used in many of the subsequent monitors produced for the US Navy during the Civil War. The type was also used as the heavy pivot gun on many sloops and gunboats in the fleet - most famously aboard USS Kearsarge which sank CSS Alabama with her 11-Inch Dahlgrens. USS Niagara and USS New Ironsides even carried 11-Inch Dahlgrens as broadside guns.

Initially designed to fire an approximately 128-pound explosive shell for use against wooden ships, the 11-Inch Dahlgren could fire an approximately 168 pound solid shot for use against ironclads and forts. The propellant charge was initially 15 pounds for both shot and shell. Following the March 1862 engagement between USS Monitor and CSS Virginia, the maximum propellant charge was increased. Bureau of Ordnance records show 25-pound charges being tested against armor in April of 1862 and 30-pound charges being tested in May of 1863. The Ordnance Instructions indicate that 20-pounds was the standard heavy charge with 30-pounds being authorized for close range engagements against ironclads.