The _Benton_ had been a snag-boat--a craft with two hulls so joined and strengthened that she could get the largest kind of a cottonwood tree between the hulls, hoist it out of the mud, and drag it clear of the steamer channel. She had had two wheels, but one between the hulls was substituted, and the whole was built over into the semblance of an angular turtle, and armored with plates of iron three and a half inches thick, well backed with oak. She was a five-knot boat and of deep draft for the service (nine feet), but she was at that date the most powerful warship afloat, and “she went by the name of the _Old War Horse_.” She carried sixteen guns, of which two were nine-inch Dahlgrens. Another vessel, like the _Benton_, was called the _Essex_, because commanded by Capt. William Porter, a son of the Porter of _Essex_ fame. “After bearing a creditable part in the battle of Fort Henry she became separated by the batteries of Vicksburg from the upper squadron, and is less identified with its history.” She carried one ten-inch and three nine-inch guns besides several smaller ones. Other vessels were added to this upper Mississippi squadron from time to time, but “they bore no proportionate share in the fighting. The eight (from the Eads’ yards) may be fairly called the ships of the line of battle on the Western waters.” Commander John Rodgers was relieved by Flag Officer Foote on September 6, 1861. He brought a number of younger officers who were to command the ships of the new fleet while taking orders from the commanding general of that department. Among these was Commander Henry Walke, who had saved Fort Pickens at Pensacola, as already told, by disobeying orders. Walke was sent to the _Taylor_. These salt-water fighters found strange materials awaiting them--ships such as they had never dreamed of in connection with war, and men from the river banks and the corn-fields who knew nothing of great guns and less, were that possible, of the restraints of naval discipline. Nevertheless, the effects of naval discipline made first-class tars out of the raw material, and the gunboats proved good enough for the occasion. [Illustration: A. H. Foote. _From a photograph._] The first actual conflict between the gun-boats and the Confederates was on September 10, 1861, when Grant (who was then under Frémont) determined to dislodge a body of Confederates stationed on the west side of the Mississippi, eight miles below Cairo, and near Norfolk, Missouri. The _Conestoga_, Captain Phelps, and the _Lexington_, Captain Stembel, were sent down. They found the Confederates had sixteen field-pieces and a considerable body of cavalry. There was a lively bit of cannonading for a time, and two Confederate gunboats (converted river steamers) came up to join in. The Confederates’ guns were silenced, and then the government gunboats returned to Cairo.