Miss Lou saw all this only as the eyes catch, half-involuntarily, what is passing before them.  With an awe almost overwhelming, her attention was absorbed by a phase of war utterly unknown to her—­an artillery duel.  Two Confederate batteries in the grove had opened and defined their positions.  The Union guns replied, shot for shot, in loud explosions, with answering, deep-toned roar.  Above the detonations were heard the piercing screams of the shells as they flew back and forth.  On the ridge they burst with a sharp crack and puff of vapor, with what effect could only be guessed; but the missiles which shrieked into the grove gave the impression of resistless, demoniacal power.  Great limbs and even tops of trees fell crashing after them.  Blending faintly with the rending sound which followed were screams and yells.

“Well,” exclaimed the girl, “if Cousin Mad is there he at least is brave.  It seems as if my knees would give way under me.”

Even as she spoke, a forked line of light burned downward athwart the heavy rising clouds.  The smoke of the battle was lurid an instant; then came a peal which dwarfed the thunder of earthly artillery.  Strange to say, the sound was reassuring to the girl; it was familiar.  “Ah!” she cried, “the voice of heaven is louder than this din, and heaven after all is supreme.  This fiery battle will soon be quenched and hot blood cooled.”

The voice in the sky was unheeded, for entering the lawn from the road, distant from the mansion about an eighth of a mile, was seen a solid gray column.  On it went toward the ridge at a sharp trot.  “Ah!” groaned Mr. Baron, “now comes the tug of war.”

The girl screamed and moaned as she saw shells tearing their way through this column, horses and men rolling over on the ground, puffs of smoke which rose revealing frightful gaps; but on flowed the dark gray torrent as if propelled by an invisible, resistless force.  Vacancies made by wounds and death were closed almost instantly.  In the strange, luminous twilight made by the approaching storm, the impetuous advance was wonderfully distinct in the distance, like a vivid silhouette.

As the head of the column drew near the gentle acclivity, it fairly seemed to crumble.  Grape shot was now making havoc; but for every man and horse that fell, two apparently came on as from an exhaustless reservoir.  High above all sounds now came a yell which, once heard, can never be forgotten, and the Confederate column deployed at a gallop, charging the ridge.  The Union skirmish line had already retired to the right, while pouring over the ridge by which they had been hitherto concealed, came rank after rank of men in blue, their deeper chest shouts blending with the shriller cries of their enemies.  Charge was being met with counter charge.  Cannon were silent, for now friends and foes were too near together.  Even the clouds loomed silently, as if in suspense, over the terrific shock of the two lines of approaching cavalry.