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USS Miantonomoh (1865)

Ironclad Monitor

USS Miantonomoh (1865)

Ironclad Monitor


USS Miantonomoh was launched during the American Civil War in 1863 but not formally commissioned until after the war in September of 1865.
National Flag Graphic
ORIGIN: United States
YEAR: 1865
SHIP CLASS: Miantonomoh-class
SHIPS-IN-CLASS (4): USS Agamenticus; USS Miantonomoh; USS Monadnock; USS Tonawanda
OPERATORS: United States

Unless otherwise noted the presented statistics below pertain to the base USS Miantonomoh (1865) design. Common measurements, and their respective conversions, are shown when possible.
CREW: 150
LENGTH: 258.5 feet (78.79 meters)
BEAM: 52.8 feet (16.09 meters)
DRAUGHT: 12.7 feet (3.87 meters)
PROPULSION: 4 x Martin boilers with engines developing 642 horsepower while driving 2 x Screws.
SPEED (SURFACE): 7 knots (8 miles-per-hour)

4 x 15" (380mm) Dahlgren smoothbore main guns


Detailing the development and operational history of the USS Miantonomoh (1865) Ironclad Monitor.  Entry last updated on 8/17/2017. Authored by Staff Writer. Content ¬©
The American Civil War (1861-1865) has been long remembered for its many land battles dotting the United States countryside but the rivers and coastal areas of the country saw their fair share of fighting thanks to the rise of the ironclad warship. Ironclads were used to rule critical rivers, harbors, and waterways en route to victory which was ultimately claimed by the North. USS Miantonomoh was an ironclad monitor born during the war years when laid down in 1862. She was launched on August 15th, 1873, but would not be commissioned until after the fighting was over - on September 18th, 1865 - leaving this Civil War ironclad with no wartime service to speak of.

USS Miantonomoh was the second ship of the Miantonomoh-class of ironclad monitors. This group included USS Agamenticus, USS, Monadnock, and USS Tonawanda.

The vessel was laid down at the New York Navy Yard (Brooklyn, New York) from a design set forth by John Lenthall. Lenthall took a slightly different approach to the new monitor by raising its freeboard (the distance from a ship's waterline to the upper deck level) which helped to increase the vessel's ocean-going capabilities at the expense of its combat survivability. T o compensate for the additionally exposed surface, oak-reinforced armor plate was added which measured several inches thick; 11 inches protected the two main gun turrets, 5.5 inches were installed along the hull sides, and the deck received 1 inch of armor protection. Displacement was 3,455 tons with dimensions being a 226 foot length, 49.3 foot beam, and 12.9 foot draught. Primary armament was 2 x 15" (381mm) Dahlgren smoothbore guns backed by 2 x 150-pounder Parrott rifled guns. Propulsion was through four horizontal back-acting engines driving a pair of screws through 642 horsepower output allowing for a maximum speed of 9 knots through cruising was typically in the 6-7 knot range. This machinery was designed by Benjamin Isherwood. The vessel's standard operating crew numbered 150 men.

Miantonomoh's profile was dominated by a single smoke funnel at amidships with each circular turret emplacement placed fore and aft of this structure. Despite its raised freeboard, the vessel still held a relatively low hull profile from the waterline which was a consistent quality of other ironclads of the war. Well armed and armored, the warship was nonetheless a plodding design with a wide turning radius - qualities also shared between many of the armored Civil War warships. Her structure supporting each turret was also constructed of wood which eventually proved a flaw in her design - prone to rotting and fracturing under the stressed of the heavy guns as well as general wear-and-tear heaped upon the supports by the salty sea.

Miantonomoh's service career formally began in 1865 - the final year of the war. She was assigned to the North Atlantic Squadron and patrolled the American East Coast lanes for a time. With the war over, she steamed from New York to Europe the following year by way of Nova Scotia/ Newfoundland before crossing the heart of the Atlantic. From the Irish coast, she landed at Cherbourg, France in June 1866 and remained in European waters while conducting various stops. She then entered the Baltic Sea for a meeting in Russia during July where she impressed observers from the Russian Navy. She then made her way to Caribbean waters before settling back stateside at League Island, Philadelphia on July 22nd.

With her ocean-going days judged firmly behind her, Miantonomoh's service to the United States Navy ended on July 26th, 1867 when she was decommissioned. However, she was quickly recommissioned for limited service once more during November 1869 and used in the funeral procession of noted philanthropist / entrepreneur Geroge Peabody in a journey from London to Massachussetts. With this endeavor now complete, Miantonomoh was decommissioned for the final time on July 28th, 1870 - this time in Boston waters. During 1874, she was moved to Pennsylvanian waters as a cover to a new American ship-building program. When this decoy mission was over her hulk was scrapped (1875) leaving just her name to the history books. Some of her remains made up the new Amphitrite-class (dubbed "New Navy" monitors) ordered in 1874 - one of the class being named USS Miantonomoh (BM-5) in her honor and serving from 1882 until 1907. This vessel is detailed elsewhere on this site.