In the river above the forts lay a Confederate war fleet of fifteen vessels, including an iron-clad ram and an iron-clad floating battery, both carrying heavy guns. This fleet had been stupidly weakened by the withdrawal of Hollins's gunboats for inconsequent service at Memphis. Below the forts was a great chain barrier stretched across the river and supported by hulks anchored in the stream for that purpose. For the protection of this barrier the shores were lined with Confederate sharpshooters--riflemen accustomed to hit whatever they might shoot at. Having got his fleet into the river after weeks of toil--leaving one very important vessel behind--it was Farragut's task to assail and overcome these defenses and force his way through a strong fleet, up the narrow river to the city he was ordered to capture. Farragut, as has been said already and as he had bluntly told the Navy Department, had no confidence whatever in the effectiveness of the mortar fleet, which was in charge of its originator, David D. Porter. He would have preferred to leave that part of his squadron behind as an entirely useless and embarrassing incumbrance; but he was a man of generous mind and never arrogantly opinionated. So he gave Porter the fullest possible opportunity to demonstrate the effectiveness of his mortar fleet. There were twenty-one of the mortar schooners, each carrying a mortar of thirteen inches caliber, which threw shells weighing two hundred and eighty-five pounds each. These shells were filled with such charges of gunpowder as made them, in theory at least, terrible engines of destruction when they exploded. It was Porter's firm conviction that by their fire alone he could compel the Confederates to abandon their forts and leave the way clear for the fleet to sail on up the river with only the Confederate war vessels to contest their passage. Farragut did not expect any such result, but he gave Porter every opportunity. Securely anchored in a position of Porter's own selection, the mortar schooners opened fire on the eighteenth of April. For six consecutive days and nights they threw their fearful missiles, each in itself a mine, into the forts. They threw in all six thousand of these shells, weighing in the aggregate no less than eight hundred and fifty-five tons. They killed or wounded only fifty men--a picket guard in numbers--or, as Dr. Rossiter Johnson has curiously calculated, they killed or wounded about one man to every sixteen tons of iron hurled into the forts. This was at the rate of only eight casualties a day, a bagatelle in war and very naturally a bombardment so slightly effective utterly failed to render the forts untenable or to drive out the brave men who were set to defend them. On the contrary the Confederate fire in response to the mortars sank one of the schooners and disabled one of the steamers. Thus was again taught the familiar lesson of war, that the terrific is not necessarily the effective fire in battle.