The boat is built like a raft, of thick timbers, laid crosswise and bolted firmly together. It is about thirty feet long and twelve wide, and has iron plates around its sides to screen the men from Rebel sharpshooters. The mortar is more than four feet in diameter. It is thicker than it is long. To fire a mortar accurately requires a good knowledge of mathematics, of the relations of curves to straight lines, for the shell is fired into the air at an angle of thirty or forty degrees. The gunner must calculate the distance from the mortar to the enemy in a straight line, and then elevate or lower the muzzle to drop his shell not too near, neither too far away. He must calculate the time it will take for the shell to describe the curve through the air. Then he must make his fuses of the right length to have the shell explode at the proper time, either high in the air, that its fragments may rain down on the encampment of the enemy, or close down to the ground among the men working the guns. It requires skill and a great deal of practice to do all this. The mortar flotilla was commanded by Captain Henry E. Maynadier, assisted by Captain E. B. Pike of the engineers. There were four Masters of Ordnance, who commanded each four mortars. Each mortar-boat had a crew of fifteen men; three of them were Mississippi flatboatmen, who understood all about the river, the currents and the sand-bars. Commodore Foote's flotilla consisted of the Benton, 16 guns, which was his flag-ship, covered all over with iron plates, and commanded by Captain Phelps; the Mound City, 13 guns, commanded by Captain Kelty; the Carondelet, 13 guns, Lieutenant Walke; the Cincinnati, 13 guns, Captain Stemble; the St. Louis, 13 guns, Captain Dove; the Louisville, 13 guns, Lieutenant Paulding; the Pittsburg, 13 guns, Lieutenant Thompson; the Conestoga, 9 guns, Lieutenant Blodgett; in all, 103 guns and 10 mortars. The Conestoga was used to guard the ammunition-boats, and took no part in the active operations. Commodore Foote had several small steam-tugs, which were used as tenders, to carry orders from boat to boat. The Southern people thought that Island No. 10 could not be taken. On the 6th of March a newspaper at Memphis said:-- "For the enemy to get possession of Memphis and the Mississippi Valley would require an army of greater strength than Secretary Stanton can concentrate upon the banks of the Mississippi River. The gunboats in which they have so much confidence have proved their weakness. They cannot stand our guns of heavy calibre. The approach of the enemy by land to New Madrid induces us to believe that the flotilla is one grand humbug, and that it is not ready, and does not intend to descend the river. Foote, the commander of the Federal fleet, served his time under Commodore Hollins, and should he attempt to descend the river, Hollins will teach him that some things can be done as well as others."[25]