The USS Cairo River Ironclad

The following text is from the National Park Service’s brochure on the U.S.S. Cairo, which is located at Vicksburg National Military Park:

Seven Ironclads in 100 Days

Meet the deadline or pay $200 a day. James B. Eads agreed to these terms for the construction of seven new ironclads. To speed production, a partner shipyard in Mound City, Illinois, built three of the boats, including the USS Cairo. Eads’ shipyard in Saint Louis built the other four. All seven were delivered in 100 days at an average cost of $101,808 each, and went on to play an instrumental role in securing the Mississippi River and its shallow tributaries.

Designed to Fight

Named after cities along the Mississippi River Valley, the City Class ironclads like the Cairo (pronounced kayroe) prowled the muddy water of the Mississippi River and its shallow tributaries. The City Class boats were 175 feet long and 52 feet wide and offered few comforts for the 176 sailors and officers that called the ironclad home. This formidable warship was equipped with 13 heavy cannon, protected by two and half inches of armor. The thickest armor surrounded the vulnerable boilers and engines located amidships (middle of the boat). The Cairo’s engines provided a top speed of six knots when traveling with the Mississippi’s current, and a meager three knots when traveling against. Under full steam, the boilers required nearly a ton of coal per hour and required frequent replenishment of the coal bunker below deck.

Raised from the murky waters of the Yazoo River in 1964, the mud and silt formed a protective barrier, leaving the Cairo and its contents in remarkable condition. The displayed ironclad still includes the original cannon, boilers, engines, hull, and armor.

Seven Sisters

From their first action at Forts Henry and Donelson in 1862, to the Red River Expedition of 1864, the formidable City Class gunboats provided valuable assistance to the Union campaign on the Mississippi River. Despite an 880-ton displacement, the gunboats drafted a mere sixfeet of water and it was said they “could navigate in a heavy dew.” The Cairo is the only surviving example of the original seven City Class gunboats.

Torpedoed and Sunk!

On December 12, 1862, the Cairo was guarding a mine-clearing expedition on the Yazoo River. Her commander, hearing small arms fire coming from up ahead, steamed around other gunboats into unexplored waters. Suddenly, explosions tore open the wooden hull. She sank quickly in 36 feet of water. No lives were lost and the crew was recovered by nearby vessels.

What sank the Cairo? Some historians believe Confederates, lying in wait along the riverbank, detonated the mines (called torpedoes in the Civil War) electrically with a crude galvanized battery. Other experts think the submerged mines were strung on a line across the channel. When the Cairo hit the line, her forward motion pulled the torpedoes against the sides of the hull where they detonated.

Discovery of the Wreck of the U.S.S. Cairo

From Wikipedia: “Studying Civil War maps, Edwin C. Bearss of Vicksburg National Military Park set out to search for the lost ship using a simple magnetic compass. With the assistance of Don Jacks and Warren Grabau, the ship was found in 1956.”Ed Bearss wrote a book about the USS Cairo in 1966 titled: Hardluck Ironclad, The Sinking and Salvage of the Cairo.