"Up, Invincibles!" cried Colonel Talbot, and they began to fire, and load, and fire again into the attacking force which had walked into what was almost an ambush. "They'll never reach the ford!" shouted Happy Tom. "Never!" Harry shouted back. The Southern generals, already trained in battles, pushed their advantages. A great force of Southern sharpshooters crossed the river and took the Northern brigade in flank. The New Yorkers, unable to stand the tremendous artillery and rifle fire in their front, and the new rifle fire on their side also, broke and retreated. But another brigade came up to their relief and they advanced again, sending a heavy return fire from their rifles, while the artillery on their flank replied to that of the South. The combat now became fierce. The Invincibles in the very thick of it advanced to the water's edge, and fired as fast as they could load and reload. Huge volumes of smoke gathered over both sides of Bull Run, and men fell fast. There was also a rain of twigs and boughs as the bullets and shells cut them through, and the dense, heated air, shot through with smoke, burned the throats of blue and gray. But the South had the advantage of position and numbers. Moreover, those riflemen on the flanks of the Northern troops burned them terribly and they were weary, too, with long marching in dust and heat. As the artillery and rifle fire converged upon them and became heavier and heavier they were forced to give way. They yielded ground slowly, until they were beyond range of the cannon, and then, brushing off the fierce swarm of sharpshooters on their flank, they retreated all the way back to the village, whence they had come. The firing on the Southern side of Bull Run ceased suddenly, and the smoke began to drift away. The Invincibles, save those who had fallen to stay, stood up and shouted. They had won the greatest victory in the world, and they flung taunts in the direction of the retreating foe. "Stop that!" shouted Colonel Talbot, striding up and down the line. "This is only a beginning. Wait until we have a real battle." "This has happened for the best," said Happy Tom, "but I'd like to know what the colonel calls a real battle. The fire was so loud I couldn't hear myself speak, and I know at least a million men were engaged. Arthur, how can you be cool enough to bathe your face in that water?" "It's to make it cool," replied St. Clair, who had stooped over Bull Run, and was laving his face. "I feel that dust and burned gunpowder are thick all over me." He stood up, his face now clean, and began to arrange his uniform. Then he carefully dusted his coat and trousers. "Hope you are all ready for another battle, Arthur," said Tom. "Not yet," replied St. Clair laughing. "That will do me for quite a while."