fortified Island Number Ten and in the attack on and spiking of shore batteries below New Madrid, Missouri, in Battle of Island Number Ten. From April through the end of June, his ship participated in the drawn-out series of operations against Plum Point Bend, Fort Pillow, and Memphis. On July 15, Commander Walke almost met his match when the Confederate ironclad ram made its move down the falling Yazoo River toward Vicksburg. Carondelet supported by and Walke's former command, Tyler, engaged the Southern ironclad. During the brisk opening exchange, Carondelet suffered heavy damage and was forced out of action in a disabled, though floating, condition. Queen of the West retreated immediately, leaving only little Tyler to face the powerful ram. The Southern warship, consequently, made it safely to the stronghold at Vicksburg. On August 4, 1862, Walke was promoted to captain and assumed command of the ironclad ram then under conversion from a river steamer at St. Louis. He put her in commission on February 27, 1863, and commanded her during the dash past Vicksburg on April 6 and during the duel with shore batteries at Grand Gulf on the 29th. That summer, his ship briefly blockaded the mouth of the Red River early in June. On July 24, Captain Walke was ordered back to the East Coast to prepare the sidewheeler for service. He put her in commission on August 18, 1863 at New York, but his command of that steamer proved brief. On September 22, he was transferred to the screw sloop , which he commanded through the final two years of the Civil War, cruising the South American coast in search of Confederate commerce raiders. On August 17, 1865, he was detached from Sacramento and returned home to await orders. Post-war years On July 31, 1866, Walke was promoted to commodore. From May 1, 1868 until April 30, 1870, he commanded the naval station at Mound City, Illinois. While waiting orders to his next assignment, Walke was promoted to rear admiral on July 20, 1870. He was placed on the retired list on April 26, 1871. However, his service to the Navy did not end, for, on that same day, he reported for some variety of special duty under the senior admiral of the Navy, Admiral David Dixon Porter. That tour lasted until October 1, at which time he was appointed to the United States Lighthouse Board.