The Casco-Class Iron Clads That Could Not Float

Stereoview of a pair of Monitor class iron clads in port, the USS Shawnee is left, and the USS Wassuc is right, likely at Charlestown Navy Yard. Men are milling about on the vessel at the right, with the city n the background. Attributed to Kilburn Brothers. Overall fine condition. These were part of the third class of monitors, called the Casco-class, developed specifically for operating along the shallow waters of the Mississippi River and it various tributaries. These vessels had a shallow draft—the portion of the hull under the water—of not more than six feet, and a freeboard—the portion of the hull above the water— of only fifteen inches. They were to be lightly armored compared to their larger cousins the Passaic and the Canonicus. The original plans were drawn by John Ericsson, but they were altered by naval chief engineer Alban Stimers, who was woefully inexperienced to the task. Stimers wanted the ships to have an even lower draft, of only four feet, but at the same time he increased the armor on the decking and turret. When the first completed vessel was put on sea trial, the deck sank below the water. To rectify the error, the hull was raised by an additional two feet, but it only added more weight to the already overweight vessel. Finally, the turret was removed and a torpedo was added. After several more trials it was concluded that the vessels were unseaworthy and completely useless. All twenty ships were scrapped.