* * * * * Then before him appeared his enemy. Tam had the sun at his back and secured a good view of the Müller machine. It was the great white dragon-fly he had seen two days before. Apparently Müller had other business on hand. He was passing across Tam's course diagonally--and he was climbing. Tam grinned. He was also pushing upward, for he knew that his enemy, seemingly oblivious to his presence, had sighted him and was getting into position to attack. Tam's engine was running beautifully, he could feel a subtle resolution in the "pull" of it; it almost seemed that this thing of steel was possessed of a soul all its own. He was keeping level with the enemy, on a parallel course which enabled him to keep his eye upon the redoubtable fighter. Then, without warning, the German banked over and headed straight for Tam, his machine-gun stuttering. Tam turned to meet him. They were less than half a mile from each other and were drawing together at the rate of two hundred miles an hour. There were, therefore, just ten seconds separating them. What maneuver Müller intended is not clear. He knew--and then he realized in a flash what Tam was after. Round he went, rocking like a ship at sea. A bullet struck his wheel and sent the smashed wood flying. He nose-dived for his own lines and Tam glared down after him. Müller reached his aerodrome and was laughing quietly when he descended. "I met Tam," he said to his chief; "he tried to ram me at sixteen thousand feet--Oh, yes. I came down, but--_ich habe das nicht gewollt!_--I did not will it!" Tam returned to his headquarters full of schemes and bright "thochts." "You drove him down?" said the delighted Blackie. "Why, Tam, it's fine! Müller never goes down--you've broken one of his traditions." "A' wisht it was ain of his heids," said Tam. "A' thocht for aboot three seconds he was acceptin' the challenge o' the Glasca' Ganymede--A'm no' so sure o' Ganymede; A' got him oot of the sairculatin' library an' he was verra dull except the bit wheer he went oop in the air on the back of an eagle an' dropped his whustle. But MacMuller wasn't so full o' ficht as a' that." He walked away, but stopped and came back. "A'm a Wee Kirker," he said. "A' remembered it when A' met MacMuller. Though A'm no particular hoo A'm buried, A'm entitled to a Wee Kirk meenister. Mony's the time A've put a penny i' the collection. It sair grievit me to waste guid money, but me auld mither watchit me like a cat, an' 'twere as much as ma life was worth to pit it in ma breeches pocket." * * * * *