The Dahlgrens of the Washington Navy Yard
9-Inch Dahlgren Number 378 manufactured by Cyrus Alger & Co. in 1862 is displayed at the Washington Navy Yard
It was at the Washington Navy Yard that John A. B. Dahlgren worked on revolutionizing United States Naval Ordnance. First assigned to the yard in 1847 and tasked with testing the new series of 32-Pounders which were just entering service, he quickly realized the limitations and weaknesses of those cannon. He created a system of shell guns epitomized by his 9-Inch and 11-Inch Dahlgren shell guns. Spurred by the lack of adequate small cannon for naval landing forces during the Mexican War, he also developed a system of boat howitzers. Dahlgren’s designs formed the core of US Naval armament during the American Civil War. It is fitting that three of his designs are displayed at the Washington Navy Yard.
As of August 2024, the three Dahlgren guns displayed at the Washington Navy Yard are:
9-Inch Dahlgren Shell Gun Number 378 manufactured by Cyrus Alger & Co. in 1862. It is marked as originally weighing 9,210 pounds. The appendix in The Big Guns states that this Dahlgren served aboard the ship of the line USS Vermont. This Dahlgren appears to be a former bollard - it shows where a bar was run through the chase (muzzle end) of the cannon in order that lines could be tied to the gun.
12-Pounder Bronze Dahlgren Boat Howitzer (Light) Number 168 manufactured at the Washington Navy Yard in 1871. The howitzer is marked as weighing 425 pounds with 25 pounds preponderance. The carriage (except for the wooden wheels) is likely original.
20-Pounder (4-Inch) Bronze Dahlgren Rifle Number 76 manufactured at the Washington Navy Yard in 1865 . It is marked as weighing 1,352 pounds. It is mounted on an original 2-truck carriage made from cast-bronze components, the design of which The Big Guns attributes to John Dahlgren (pg. 108). The appendix in The Big Guns states that this rifled Dahlgren served abord USS Colorado. Note that unlike Dahlgren boat howitzers, this rifled cannon has trunnions. According to this article, this Dahlgren rifle was placed on display at the museum in 1968 - having previously been displayed at the Coast Guard Base at Curtis Bay, Baltimore, Maryland (where 3 or 4 similar Dahlgren rifles may remain?)
As a new National Museum of the United States Navy is constructed over the next several years, I sincerely hope that the two 11-Inch Dahlgren shell guns carried aboard USS Kearsarge will be displayed there. (They are currently in a Naval History and Heritage Command warehouse in Richmond, Virginia.)
12-Pounder Bronze Dahlgren Boat Howitzer (Light) Number 168 manufactured at the Washington Navy Yard in 1871.
20-Pounder (4-Inch) Bronze Dahlgren Rifle Number 76 manufactured at the Washington Navy Yard in 1865 .
Note the scar on the side of the chase of the 9-Inch Dahlgren Number 378 - showing this cannon to be a former bollard.
9-Inch Dahlgren installed as a bollard around a former dry dock at Boston. Notice the Fletcher-class destroyer and museum ship Cassin Young and the masts of the frigate USS Constitution in the background. This is one of several 9-Inch Dahlgrens still present as bollards around the dock. (Photo taken in August of 2024.)
Postwar photo of USS Vermont at New York. Note the Dahlgren boat howitzer in the foreground. Naval History and Heritage Command Photo: https://www.history.navy.mil/content/history/nhhc/our-collections/photography/numerical-list-of-images/nhhc-series/nh-series/NH-93000/NH-93915.html
Diorama of the Battle of Hampton Roads at the National Museum of the United States Navy at the Washington Navy Yard. The diorama shows the crew of USS Minnesota firing upon CSS Virginia. The pivot gun would be a 10-Inch Dahlgren - of which there are no known survivors. The Dahlgren on the broadside Marsilly (two wheel) carriage looks like a 9-Inch Dahlgren.
