USS Niagara’s Armament
USS Niagara is seen at the Charlestown Navy Yard (Boston) during the American Civil War. This photo seems to show Niagara after (or near the conclusion of) her refit, and the ports do appear near the waterline. (Library of Congress Photo: 2016863463 )
USS Niagara is seen at the Charlestown Navy Yard (Boston) during the American Civil War. As built Niagara carried a peculiar armament - twelve 11-Inch Dahlgrens all mounted on her spar deck. If I understand correctly (and correct me if I am wrong), only the fore and aft pivots could fire on either broadside, giving her an ability to fire up to seven 11-Inch Dahlgrens port or starboard. In 1862 she was taken out of service.
Intriguingly, ten of USS Niagara's Dahlgrens were transferred to become the majority of the battery of USS New Ironsides. 11-Inch Dahlgrens Registry Numbers 1, 2, 3, 4, 5, 8, 9, 10, 30, and 31 served on both both ships in this way. (Record Group 74, Entry 111 "Records of the Armament of Naval Vessels, 1842–1903" Vol 2. Pp. 48, 292, 348).
Niagara was refitted with a truly fearsome battery in 1862-1863, emerging carrying twenty 11-Inch Dahlgrens (a consecutive set of Nos. 262-281 from Cyrus Alger) on her gun deck and twelve 150-Pounder Parrotts on her spar deck: giving her a maximum broadside of ten 11-Inch Dahlgrens and seven 150-Pounder Parrotts.
This was the heaviest battery to be fitted to any ship to see service during the war. However, it was too heavy for the ship. Her commanding officer reported that this left the gun deck ports only 5 feet 6 inches above the waterline, causing flooding even in a minor swell. Her gun deck Dahlgrens would be removed in 1864, leaving only the spar deck Parrotts, and it was with this battery that her captain declined action against CSS Stonewall off the Spanish coast in March of 1865. (See Canney "Frigates, Sloops, and Gunboats" Pp. 52-59.)
“XI-Inch Gun Carriage For US Steamer Niagara” - National Archives https://catalog.archives.gov/id/518072556
USS Niagara after her 1863 refit. Cropped from Naval History and Heritage Command Photo: NH 75895
USS Niagara’s Armament as originally built. National Archives RG 74 Entry 111
USS Niagara’s Armament as refitted in 1863. National Archives RG 74 Entry 111
USS New Ironsides Armament Page. National Archives RG 74, Entry 111
