"Whir-r-r-r!" Himmelman had opened fire while nose-diving at terrific speed. Already the victim seemed to be in his clutch, when, just as suddenly, from the same cloud in which the German air-fiend himself had found ambush, another speck appeared, swooping like a hawk with its talons ready to strike. It was Dastral, who had waited and waited, in the biting cold and the clinging moisture of the wet cloud; waited at 12,000 feet near the edge of the cloud.

He had seen Himmelman coming, had watched him like a tiny speck seeking shelter in the same misty vapour. How Himmelman had failed to discover his enemy was a mystery. They were both invisible to the combatants, it is true, and Dastral had used a dozen devices to keep himself out of sight of the Boche, though ready at any moment to fight with him.

There can be little doubt, however, that Himmelman had been watching the fight so closely that he had never even dreamt of finding his chief enemy so close at hand. Besides, no one had ever dared to imitate his tactics before, and his first intimation of Dastral's presence was when, during his wild swoop, having half emptied his first drum at the Squadron-Commander, he suddenly heard machine-gun bullets whizzing about his own ears, and felt a stinging sensation in his right arm. Looking round, he saw that the dark cloud in which he had been hiding had given birth to another air-fiend, and in that moment Himmelman knew that he was no longer the Master-Pilot of the Skies.

"Gott in Himmel!" he gasped, and made one last effort to manoeuvre.

With his hand upon the gun, and his feet upon the rudder bar, he flattened out, and tried to fight his enemy from below, leaving his last victim to limp away to safety.

But Dastral was too quick, for he had time to give the Fokker two full drums before he also flattened out just above the monoplane. He knew the Fokker had its gun fixed forward, rigidly fixed, so that it could only fire ahead through the propeller. All this he had coolly calculated beforehand. Unless, therefore, Himmelman could manoeuvre to get his enemy directly ahead, he could do nothing. Still, though wounded, the German fought on. Round and round spun the machines, over and under they went, like a shoal of porpoises, each trying to get the advantage.

Up there at 9,000 feet they performed the most amazing gymnastic gyrations and contortions. Once the German got the advantage, and was about to open a new drum of fire, when Dastral, pulling over the joy-stick, and with clenched teeth, muttered:

"No, you don't! By all the saints, no!"

And, with that, he dived under the air-fiend, and emptied his seventh and last drum into him from beneath.

It, was the end of the great fight, for with his fuselage ablaze from end to end--for his petrol tanks had been pierced--and with a bullet through his brain, Himmelman went down in a spinning nose-dive to the earth.