Pook's Turtles: The Union's City-Class Ironclad Gunboats

By Donald J. Roberts II

With the opening of hostilities between the North and South, General Winfield Scott and President Lincoln devised the “Anaconda Plan.” Its purpose was to squeeze the Confederacy into submission. Blockading the South’s seaports and gaining control of the Mississippi River were at its heart.

Sealing off Southern seaports was supposed to cause economic ruin in the South, which in turn would diminish the Confederacy’s ability to wage war. Gaining control of the Mississippi River was to have more of a direct impact on military strategy, however.

If Union forces in the West were to penetrate into Confederate territory as planned, it was critical that they obtain control of the river. If the North could not, it would be forced to defend extended lines of land communication.

The USS Corondelet, one of seven purpose-built Union river gunboats of the City-class commissioned in January 1862, also known as “Pook’s Turtles” after naval architect Samuel Pook.

As the war progressed, Confederate guerrillas became skilled at destroying Union road and rail communications. Consequently, it became increasingly important for the Union to capture the Mississippi River. At the same time, securing the river would sever the Southern states into two parts, making it difficult for Texas, Louisiana, and Arkansas to supply the eastern portion of the Confederacy with men, food, and other materials of war.

Scott wanted to build an army of at least 60,000 troops, plus a flotilla of gunboats, and then establish a line of depots along the Mississippi as he pushed his forces south down the river. He hoped that by using the river to outflank enemy positions, it would be easier to eliminate them from the struggle. Scott’s plan envisioned this northern Union force eventually linking up with the Union squadrons blockading the Gulf Coast, thus severing the Confederacy and enveloping the two parts.

Lincoln authorized the construction of ironclad gunboats for Scott’s offensive in August 1861. Not wanting to delay his attacks, Scott settled for hastily converted commercial steamers to support his combined operations along the western waterways. Three wooden side-wheelers were fitted with five-inch-thick oak planks for protection—which only proved effective against musket balls. When possible, barges tied to the sides of each “timberclad” protected the hull and paddlewheels.

When General Ulysses S. Grant attacked Belmont, Missouri, on the Mississippi River, on November 7, 1861, he had with him two of the three original conversions: the Tyler and the Lexington. They averaged 180 feet in length, 42 feet in the beam, and six feet of draft when fully loaded. Each could reach a speed of 7 to 10 knots. All were armed with smoothbore guns. The Lexington had two 32-pounders and four 8-inch guns and the Tyler had one 32-pounder and six 8-inch guns. The third boat, the Conestoga, was off patrolling the Tennessee and Cumberland rivers. It was armed with four 32-pounders.

The USS Tyler, a merchant steamboat converted to a “timberclad” gunboat in 1861, with two mortar rafts tied up along the shore of the Mississippi River.

Following these wooden stopgaps, the first purpose-built Union river gunboats launched in January 1862. The City-class ironclads, designed by Samuel M. Pook and nicknamed “Pook’s Turtles” due to the shape of their sloped casemate armor, included the Cairo, Carondelet, Cincinnati, Louisville, Mound City, Pittsburg, and St. Louis (later renamed the Baron De Kalb). All were armed with an array of 13 heavy cannons and rifled guns.

To serve as crew members on these early gunboats as well as on some of the newer models, the Department of the Navy ordered some 500 seamen from eastern seaports to serve along the western waterways. These experienced sailors from Boston and Philadelphia gave officers like Com. Henry Walke a huge advantage on the rivers.

During combined operations, the gunboats came under the direct command of army officers in the field. The most difficult aspect of this arrangement was the failure of effective communication between the army general and naval commander. However, as the war progressed, communications between each branch improved. Possibly the biggest reason for this improvement was that army commanders came to realize how decisive riverboats could be if used effectively in battle.