All around Petersburg, at such distance that the firing did not very seriously affect the little city, stretched the earthworks of the combatants. Before the end there were forty miles of earthworks. The Confederates established a line of defence. The Federals established a line of attack, and gradually, by superior strength, drove their antagonists back. Lee retired to a new series of defences, where the fight was continued. The Federals had a railway running to City Point, eleven miles away, where their ships brought for them the amplest supplies. Lee depended upon the railways which communicated with distant portions of Confederate territory. These it was the aim of Grant to cut, so that his adversary might be driven by want of food from his position. The outposts of the armies were within talking distance of each other. The men lay in rifle-pits or shallow ditches, watching opportunity to kill. Any foe who incautiously came within range died by their unerring fire. For ten long months the daily occupation of the combatants had been to attack each the positions of the other. The Confederates, by constant sallies, attempted to hinder the advance of their powerful assailant. Grant never relaxed his hold. He “had the rebellion by the throat,” and he steadily tightened his grasp. By City Point he was in easy communication with the boundless resources of the North. Men and stores were supplied as he needed them by an enthusiastic country. On the rebel side the last available man was now in the field. Half the time the army wanted food. Desertions abounded. It was not that the men shunned danger or hardship, but they knew the cause was hopeless. Many of them knew also that their families were starving. They went home to help those who were dearer to them than that desperate enterprise whose ruin was now so manifest. The genius of Lee was the sole remaining buttress of the Confederate cause. Once the Federals ran an enormous mine under a portion of the enemy’s works. In this mine they piled up twelve thousand pounds of gunpowder. They had a strong column ready to march into the opening which the explosion would cleave. Early one summer morning the mine was fired. A vast mass of earth, mingled with bodies of men, was thrown high into air. The Confederate defence at that point was effaced, and the attacking force moved forward. But from some unexplained reason they paused and sheltered themselves in the huge pit formed by the explosion. The Confederates promptly brought up artillery and rained shells into the pit, where soon fifteen hundred men lay dead. The discomfited Federals retired to their lines. * * * * *