"What was the matter?" he demanded, the ends of his moustache twitching nervously. "Don't know, sir. He kept droppin' back. I swung alongside but I couldn't savvy his signals. He kept pointin' back at his tail. I couldn't see anything wrong, but there's a big 'drome at Vitry and he signaled me that he was goin' down. I hung around to watch his landin' and then hustled back to my flight." "Fuel up, fly back there and see what's wrong," Cowan ordered. "I've a sneaky suspicion that he wasn't as bad off as he made out." As Yancey turned toward his ship, McGee came up, smiling with pleasure over the success of the flight. "Just a minute, Yancey!" Cowan called. "I've changed my mind. You needn't go back." He drew McGee to one side. "Do you remember passing over the French 'drome outside of Vitry?" he asked. "Yes, sir." "Your plane is in good order?" "Yes, sir." "Good. Yancey tells me that Siddons was forced down there. I want you to refuel, go back there and see what the trouble was. I have my own ideas." "Yes?" McGee queried. "That fellow hates formation flying like the devil hates holy water," Cowan answered. "He's a joy-rider. He knows how anxious I am to effect this move without a hitch, and he also knows there'll be no passes into Epernay to-night. I've a hunch Vitry looked good to him. I want you to find out." "Very well, sir." "I'm sending you," Cowan explained, smiling faintly, "because it doesn't make so much difference if you get lost, since you are merely 'also along', and also because I don't expect you to get lost. Report to me upon your return." "Yes, sir." 3 The mission was not particularly pleasing to McGee. Chasing around after Siddons was not his idea of a riotous time. It was some fifty-five kilometers back to Vitry, but with a good tail wind he made it in quick time. The French major in command of the squadron stationed there was exceedingly gracious. Yes, the American had landed, he told McGee, but he had taken off again within the hour. The trouble? Well, he complained that his rudder was jamming, but the mechanics could not find anything wrong. He had said, also, that his motor was running too hot. Perhaps, the major suggested, with an understanding smile, this one had rather fly alone, _hein_? So many of them would--and especially by way of Paris, or other good towns. Yes, he had given his destination--La Ferte sous Jouarre, but is not that on a direct line for Paris, Monsieur? These youthful ones, would they never learn that this was a serious business? But no, Monsieur, they are young, and how can you make one fear discipline who daily faces death? Poof! It was the grave problem.