USS ''Napa'' was a ''Casco'' class twin-screw light draft

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built during the

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for operation in the shallow inland waters of the

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. These warships sacrificed

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for a shallow

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and were fitted with a

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compartment designed to lower them in the water during battle.

Construction

The single-turreted ''Napa'' was built by the Harlan & Hollingsworth Co.,

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, and launched 26 November 1864. Though the original designs for the ''Casco''-class monitors were drawn by

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, the final revision was created by Chief Engineer Alban B. Stimers following

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Samuel F. Du Pont's failed bombardment of

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in 1863. By the time that the plans were put before the Monitor Board in

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, Ericsson and Stimers had a poor relationship, and Chief of the

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John Lenthall had little connection to the board. This resulted in the plans being approved and 20 vessels ordered without serious scrutiny of the new design. $14 million US was allocated for the construction of these vessels. It was discovered that Stimers had failed to compensate for the armor his revisions added to the original plan and this resulted in excessive stress on the wooden hull frames and a freeboard of only . Stimers was removed from the control of the project and Ericsson was called in to undo the damage. He was forced to raise the hulls of the monitors under construction by nearly two feet and the first few completed vessels had their turrets removed and a single pivot-mount 11 inch Dahlgren cannon mounted. These same few vessels had a retractable

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added as well.

Torpedo vessel conversion

As a result, ''Napa'' was converted to a torpedo vessel, 25 June 1864 and turned over to the government upon her completion 4 May 1865. Never commissioned, she was laid up at

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, PA, until 1875 when she was broken up by John Roach at New York. While at League Island, her name was changed twice: to ''Nemesis'', 15 June 1869; and back to ''Napa'', 10 August 1869.

References

{{DEFAULTSORT:Napa Casco-class monitors Torpedo boats of the United States Navy Ships built by Harlan and Hollingsworth 1864 ships