Pope's judgment in this case was good and fortune, too, favored him. Before the last of his men had left the Rapidan Lee himself, with his staff officers, climbed to the summit of Clark's Mountain. They were armed with the best of glasses, but drifting fogs coming down from the north spread along the whole side of the mountain and hung like a curtain between it and the retreating army. None of their glasses could pierce the veil, and it was not until nearly night that rising winds caught the fog and took it away. Then Lee and his generals saw a vast cloud of dust in the northwest and they knew that under it marched Pope's retreating army. The Southern army was at once ordered forward in pursuit and in the night the vanguard, wading the Rapidan, followed eagerly. Dick and his comrades did not know then that they were followed so closely, but they were destined to know it before morning. The regiment of Colonel Winchester, one of the best and bravest in the whole service, formed a part of the rearguard, and Dick, Warner and Pennington rode with their chief. The country was broken and they crossed small streams. Sometimes they were in open fields, and again they passed through long stretches of forest. There was a strong force of cavalry with the regiment, and the beat of the horses' hoofs made a steady rolling sound which was not unpleasant. But Dick found the night full of sinister omens. They had left the Rapidan in such haste that there was still a certain confusion of impressions. The gigantic scale of everything took hold of him. One hundred and fifty thousand men, or near it, were marching northward in two armies which could not be many miles apart. The darkness and the feeling of tragedy soon to come oppressed him. He listened eagerly for the sounds of pursuit, but the long hours passed and he heard nothing. The rear guard did not talk. The men wasted no strength that way, but marched stolidly on in the moonlight. Midnight passed and after a while it grew darker. Colonel Winchester and his young officers rode at the very rear, and Pennington suddenly held up his hand. “What is it?” asked Colonel Winchester. “Somebody following us, sir. I was trained out on the plains to take notice of such things. May I get down and put my ear to the ground? I may look ridiculous, sir, but I can make sure.” “Certainly. Go ahead.” Pennington sprang down and put his ear to the road. He did not listen long, but when he stood up again he said: “Horsemen are coming. I can't tell how many, but several hundreds at least.” “As we're the very last of our own army, they must be Southern cavalry,” said Colonel Winchester. “If they want to attack, I dare say our boys are willing.” Very soon they heard clearly the gallop of the cavalry, and the men heard it also. They looked up and turned their faces toward those who must be foes. Despite the dimness Dick saw their eyes brighten. Colonel Winchester had judged rightly. The boys were willing.