This information, as they now knew, was the best credential possible, and they were soon the center of an admiring crowd. Somehow the determined matter of fact and positive way which the boys adopted had the effect of winning their way, and it was thus that they had the satisfaction of entering a service which it is a most difficult thing to do even with the best credentials. The happiness of the boys was complete when their new friend told them to get up on the machine, and help him to take out the engine. Coats came off in a hurry, and they looked around for some substitute to protect their clothing. Their friend supplied the necessary articles at once remarking as he did so that he ought to know their names. After this information was supplied, he remarked: "My name is Martin; Bill Martin, Fifth Aviation Corps; don't forget the Corps or you may have trouble in getting into the grounds; and, by the way, how did you happen to get through?" "If you mean the gates, why, we just walked right through," said Alfred. "Just as though you had a right to do so!" said Martin, as he again commenced to laugh. "You said you were up in an airplane; where was that?" "Up at Dunkirk, and back of the firing line, south of the St. Quentin," said Ralph. "Do you know Tom Watkins?" asked Alfred. "Do I know Tom? Why, we came over together; poor fellow, he got a bad fall," said Martin. "We heard about it and saw him at the hospital today," said Alfred. "You don't say? So you've been flying with Tom? I'm glad to know that," said Martin, as he nodded his head approvingly. CHAPTER VII BOUND FOR VERDUN For three days more the boys wandered about Paris,--three days of the most fearful suspense; and then began the battle of the Marne. Every airplane in and about Paris was at the front, on the line somewhere, and the boys were deprived of the opportunity to see the new friend they had made at the Bois de Boulogne station. They were so sure of being able to go to Verdun that Albert wrote to his father of their plans, in the hope that he would consider it wise to leave Switzerland for that point, where they might meet. The Germans had been defeated; Paris was safe, the French line having held firmly all the way to Verdun. The determination to go there was firmly fixed in their minds, but they could see no way to accomplish the purpose. A visit to Tom at the hospital only resulted in their being told that the lieutenant was in the field, no one knew where. "I have an idea," said Ralph, as they emerged from their room one morning. "What is it?" asked Alfred. "We might get attached to the Red Cross some way, and that would be sure to take us to the front," replied Ralph. "That would be just as hard as to get in with the flying people," answered Alfred. "That may be so, too, but I can't see any other way."