Clem’s very brief glance at the driver of the Red Cross car had caused him to start and wonder. He hardly knew why he gazed after the car with an unpleasant feeling, and then, in order to watch its movements, crossed the road and swung himself up on a branch of a low tree. There were no other cars on the hill and apparently no other people, but the army ambulance man. Clem was cogitating: “Now, can’t I think where? What had Don Richards said only yesterday? Spies? But would they dare again to come here boldly and--” his thoughts were cut short. A man got down from the long, low car and quickly went to the other machine. He paused and looked about for a moment, then raised the hood and seemed to be working rapidly. He put down the hood and returned. Then the Red Cross car moved on rapidly up the hill to the far end of the lane, where it turned across pasture ground and veered about among the rocks and thickets, stopping presently on the south-east slope. “Fire and flinders! It is--it is!” exclaimed Clem. “They wouldn’t dare to go so far east and expose themselves to the guns unless the Huns knew and approved of it.” The boy dropped to the ground and, taking pad and pencil from his pocket, wrote the following: “I beg leave to report that I have this moment discovered the Hun spies we were after yesterday. They have gone to the eastern side of Hill 165, probably to signal the German lines, as reported before. I also saw them disable an army ambulance. Fearing to fail in their arrest, and confident that I can accomplish this with the aid of the ambulance man on the hill, I take the liberty of delaying my return to post. Will report as soon as possible. CLEMENT STAPLEY, Corporal.” This sheet he folded, addressed, and handed to his companion, Martin. The ambulance had a new spark plug and was ready to start. “Give this to the lieutenant as soon as you get in,” Clem said. “Now, please don’t ask any questions. I’m on an expedition the captain ordered yesterday and the lieutenant knows about it. You might tell him I said so. And, by the way, got any extra cartridges for your pistol? I might need them. I left mine in my kit. Will pay you back when I get back.” “Maybe I could help you,” began Martin, but Clem backed off. “No; I can handle this. Nothing much. When I come in I think you’ll see me bringing some Heinies along--pretty soon, too.”