The question now was where next they should meet each other in arms. Lee had chosen the field of the first onset. It was for Grant to choose the next. And in pursuance of his strategy Grant determined to move by his left flank to Spottsylvania Court House, hoping to reach that position before his adversary could get there, and to seize upon its best strategic points. In that position he would still have the great waterways at his back as a support, and a trustworthy source of supply. His desire was throughout the campaign to thrust his army in between the Army of Northern Virginia and Richmond, and this seemed to be his best opportunity to do so. He had somewhat a shorter line of march, and moreover by taking the initiative he was able to start first. If he was baffled in the attempt it was only by reason of the alertness of Lee's genius which penetrated his purpose, grasped his thought, and promptly acted in contravention of it. Spottsylvania Court House lay fifteen or sixteen miles southeast of the Wilderness battlefield, and nearly that far southwest of Fredericksburg. In order that the movement might be made without danger of his army being attacked while in motion, Grant adopted the plan of using the troops on his right as the advance force of his movement towards the left. He did this throughout that campaign by the left flank, always withdrawing the forces on his right, passing them in rear of his main army, and thus making of the movement what is technically known as a countermarch. In this way the advancing troops had always the main army between them and the enemy until they cleared the position occupied, and were well on march toward the new one aimed at. After that, of course, they must take care of themselves, but in the meanwhile the march was begun without discovery on the part of the enemy.