On April 29, 1861 Secretary of the Navy Gideon Welles received correspondence from James Eads concerning the viability of converting Submarine No.
7 into a riverine warship for the U.S. military.
Submarine No.
7 was a snagboat built by the US Navy that had been purchased by Eads' Missouri Wrecking Company and modified to raise sunken steamboats on the Mississippi River.
Both hulls of Submarine No.
7 were divided into 7 watertight compartments and Eads argued that the vessel could suffer up to 20 penetrating shot into 4 of these compartments and still stay afloat. (
Other sources state she was built with 40 watertight compartments.)
 Additionally he argued that the vessel would be able to support a strong battery of 32-pounder cannons.
His initial proposal called converting the vessel into a Cotton-clad gunboat for a cost of $3,000 in cotton.
His letter also described a plan to convert two other, smaller vessels and to create a naval base at Cairo, IL.

Lacking the resources to undertake the project, Welles forwarded Eads's letter to the Secretary of War Simon Cameron.
Cameron was impressed by the proposal and forwarded it to General George McClellan to implement the construction of the base.
Instead of the cotton-clad boat however, the US Army wanted a fleet of new ships; this became the City-class ironclad fleet.

Impressed by the Eads' abilities during the construction of the City-class,he earned several additional contracts.
One of these involved Submarine No.
7.
Eads widened Submarine No.
7 lower deck into a gun deck then added a second tier of accommodations.
The large size of the finished vessel and this additional space led to the vessel being well suited to a flagship role.
Commander William D. Porter complained that the finished vessel was too slow, and history has recorded that Eads replied that she was still fast enough to fight in.
Now as the Benton she would serve as a flagship for most of the war.
On April 29, 1861 Secretary of the Navy Gideon Welles received correspondence from James Eads concerning the viability of converting Submarine No. 7 into a riverine warship for the U.S. military. Submarine No. 7 was a snagboat built by the US Navy that had been purchased by Eads' Missouri Wrecking Company and modified to raise sunken steamboats on the Mississippi River. Both hulls of Submarine No. 7 were divided into 7 watertight compartments and Eads argued that the vessel could suffer up to 20 penetrating shot into 4 of these compartments and still stay afloat. (Other sources state she was built with 40 watertight compartments.)  Additionally he argued that the vessel would be able to support a strong battery of 32-pounder cannons. His initial proposal called converting the vessel into a Cotton-clad gunboat for a cost of $3,000 in cotton. His letter also described a plan to convert two other, smaller vessels and to create a naval base at Cairo, IL.
Lacking the resources to undertake the project, Welles forwarded Eads's letter to the Secretary of War Simon Cameron. Cameron was impressed by the proposal and forwarded it to General George McClellan to implement the construction of the base. Instead of the cotton-clad boat however, the US Army wanted a fleet of new ships; this became the City-class ironclad fleet.
Impressed by the Eads' abilities during the construction of the City-class,he earned several additional contracts. One of these involved Submarine No. 7. Eads widened Submarine No. 7 lower deck into a gun deck then added a second tier of accommodations. The large size of the finished vessel and this additional space led to the vessel being well suited to a flagship role. Commander William D. Porter complained that the finished vessel was too slow, and history has recorded that Eads replied that she was still fast enough to fight in. Now as the Benton she would serve as a flagship for most of the war.
USS Benton