The Pook Turtles, or City-class gunboats to use their semi-official name, were war vessels intended for service on the Mississippi River during the American Civil War. They were also sometimes referred to as "Eads gunboats." The labels are applied to seven vessels of uniform design built from the keel up in Carondelet, Missouri shipyards owned by James Buchanan Eads. Eads was a wealthy St. Louis industrialist who risked his fortune in support of the Union.
The City-class gunboats were the United States' first ironclad warships.
The gunboats produced by Eads formed the core of the US Army's Western Gunboat Flotilla, which later was transferred to the US Navy and became the Mississippi River Squadron. Eads gunboats took part in almost every significant action on the upper Mississippi and its tributaries from their first offensive use at the Battle of Fort Henry until the end of the war.
Early connection between Eads and the US government
In the early days of the Civil War, before it was certain that the secession movement had been thwarted in St. Louis, Missouri and before it was known that Kentucky would remain in the Union, James B. Eads offered one of his salvage vessels, Submarine No. 7, to the Federal government for conversion to a warship for service on the western rivers. In a letter he wrote to Secretary of the Navy Gideon Welles, he pointed out that the catamaran-type hull of his boat was already divided into several watertight compartments, and therefore could sustain numerous hits by enemy artillery without danger of sinking. As the interior of the country was the responsibility of the Army and not the Navy, Welles passed the letter on to Secretary of War Simon Cameron, who in turn referred it to Major General of Volunteers George B. McClellan for consideration. McClellan was commander of the Department of the Ohio, with responsibilities that included defense of the Ohio River and the parts of the Mississippi that were not in Confederate control.
At about the same time that McClellan received the letter, he also had a naval officer, Commander John Rodgers, added to his staff. Rodgers came with orders to provide the department with gunboats, either by acquiring civilian craft and converting them, or by having them built from the keel up. As the Eads letter meshed with the orders carried by Rodgers, McClellan passed responsibility on to him, ordering him to St. Louis to consult with Eads and see if his ideas were feasible. Rodgers did not like Submarine No. 7, but his negative assessment was overruled by Major General John C. Fremont, who succeeded McClellan when the latter was called to Washington to serve as General-in-Chief. Although Rodgers had opposed Eads's proposal, the two men were able to work together. This was the beginning of their short-lived but productive collaboration.
City-class gunboats; Pook Turtles
In furtherance of Rodgers's orders, he and Eads drew up a set of requirements for a fleet of armored gunboats that would operate on the Mississippi. Rodgers knew, as his colleague did not, the characteristics that would be required for a successful war vessel. Eads's contribution was equally vital, as he knew the characteristics of boats that could operate on the Mississippi, and also how to assemble the industry to build them. Together, they decided that the gunboats should have adequate armor to withstand direct shot from the artillery of the day; speed sufficient to be able to move against the current; shallow draft; and enough guns to present a serious and credible threat to the enemy. Not stated but well understood was the necessity of providing adequate accommodations for the crew, who would likely be forced to fight inside the protective shell of armor in the heat of a Southern summer.
To assist in the design of a vessel that would satisfy all of these requirements, Rodgers called for help from John Lenthall, the head of the Navy Department's Bureau of Construction, Equipment, and Repair. Lenthall provided some preliminary plans, but he had to devote most of his attention to ocean-going ships, so he withdrew. Fortunately, he was able to provide a substitute. The Navy Department already had under contract a man who had experience in designing river craft, one Samuel M. Pook, working at the time in Cairo, Illinois.