When Bazaine reached Metz with his army he discovered that the railway running north had been cut, and that he was surrounded. Two German armies, numbering 160,000 men, were left to hem him in and wait until starvation drove him to surrender. Two other armies were sent to meet MacMahon, who was supposed to be at Châlons. The cavalry, however, soon discovered that Châlons was deserted; MacMahon had marched north, with what purpose could only be guessed. The cavalry hunted the country for him, and at last found him trying to reach Metz so as to relieve Bazaine. Had he pushed on with all speed he might have relieved Metz, and, with the troops in that city, have formed a strong army which could have faced the German legions once more. But he had wasted ten precious days on the road, and this gave the Germans time to catch him up. They came upon him unawares, for his watch had been carelessly kept, and his men were cooking their dinners as the advance guards of the enemy burst upon them. MacMahon found to his dismay that the Germans were between him and Metz and that he was obliged to retreat. They drove him northwards to the town of Sedan,[134] which you will find on the Meuse, in a corner of the country from which there was no escape unless he crossed the Belgian border. He might have done this and avoided the onslaught of the Germans; but, as you know, the French had promised that they would not trespass on Belgian soil, and they kept their word, though it cost them dear. Through the dark night, amidst a heavy downpour of rain, the men toiled along the heavy roads in great confusion, and reached Sedan at nine next morning. The Emperor, who was following MacMahon's army, arrived late at night, without baggage or escort, and walked almost alone from the railway station to the little town. Next day MacMahon tried to restore some sort of order in his ranks and prepare his forces to meet the enemy; but by nightfall the two German armies had so completely hemmed them in that he could neither hope to break through nor escape if defeated. His army was massed under the walls of Sedan in a valley known as the Sink of Givonne,[135] in a sort of horse-shoe line, concave to the enemy. At five the next morning, on all the hills around, appeared the dark masses of the German troops. Two hundred and fifty thousand men were in a circle on the heights round the Sink of Givonne. They had come as stealthily as serpents. They were there when the sun rose, and when the French saw them they knew that all was over. The German guns commanded every part of the crowded valley, and when they opened fire the result was a massacre. One of the first to fall was MacMahon, who was struck down by a bursting shell, and was carried from the field. Another commander took his place, but no general, however great, could save the French army, which was now a helpless, beaten mob.