Jackson had invented a "foot cavalry." McGruder had supplemented it by a "foot navy." At Murfreesboro, Tennessee, on the same day General Bragg had engaged the army of Rosecrans and fought one of the bloodiest engagements of the war. Its net results were in favor of the Confederacy in spite of the fact that he permitted Rosecrans to move into Murfreesboro. The Northern army had lost nine thousand men, killed and wounded, and Bragg carried from the field six thousand Federal prisoners, thirty pieces of artillery, sixty thousand stand of small arms, ambulances, mules, horses and an enormous amount of valuable stores. His own losses had been great but far less than those he inflicted on Rosecrans. He had lost one thousand two hundred and ninety-two killed, seven thousand nine hundred and forty-five wounded and one thousand twenty-seven missing. At Charleston a fleet of iron-clads on the model of the _Monitor_ had been crushed by the batteries and driven back to sea with heavy loss. The _Keokuk_ was left a stranded wreck in the harbor. A second attack on Vicksburg had failed under Sherman. A third attack by Grant had been repulsed. Farragut's attack on Port Hudson had failed with the loss of the _Richmond_. The Federal Government now put forth its grandest effort to crush at a blow the apparently invincible army of Davis' still lying in its trenches on the heights behind Fredericksburg. Hooker's army was raised to an effective force of one hundred and thirty thousand and his artillery increased to four hundred guns. Lee had been compelled to detach Longstreet's corps, comprising nearly a third of his army for service in North Carolina. The force under his command was barely fifty thousand. So great was the superiority of the Northern army Hooker divided his forces for an enveloping movement, each wing of his being still greater than the whole force under Lee. Sedgwick's corps crossed the river below Fredericksburg and began a flanking movement from the south while Hooker threw the main body across the Rappahannock at three fords seven miles above. On April thirtieth, he issued an address to his men. His forces were all safely across the river without firing a shot. He had Lee's little army caught in a trap between his two grand divisions. In his proclamation he boldly announced: "The operations of the last three days have determined that our enemy must ingloriously fly, or come out from behind their defenses and give us battle on our own ground, where certain destruction awaits him." His enemy was not slow in coming out from behind his defenses. With quick decision Lee divided his little army by planting ten thousand men under Early on Marye's Heights to stop Sedgwick's division and moved swiftly with the remainder to meet Hooker in the dense woods of the Wilderness near Chancellorsville.