Giving a hasty glance round Blake took in the situation. The remaining Fokkers had been disposed of by the British biplanes, but not before one of the latter had to make an involuntary landing with its petrol tank perforated like a sieve and its observer badly wounded. There was now a fair chance of matching Blake's battleplane against the vaunted and possibly overrated Fokker.

The latter, with clouds of smoke pouring from her exhaust, was making off towards her own lines. Before gaining shelter she would have to pass over the British trenches less than thirty miles from the encounter, even if she were successful in throwing off pursuit.

Blake was equally determined to smash his opponent long before the latter came within sight of the German trenches. It was essential that in this early stage the secret battleplane should not show herself to the Huns over their own lines. The systematic disappearance of the "star" enemy airmen, without any hint of the nature of their destruction, would have a telling effect upon the morale of their flying men. It was a parallel case to the steady and unannounced decrease in the number of German submarines, scores of which left port never to return, and leaving no record of their disappearance save that known and jealously guarded by the British Admiralty.

"Now see what you can do, Athol," exclaimed Blake, as the battleplane, gaining upon her antagonist hand over fist, was in a favourable position to open fire.

Glancing along the sights Athol pressed the thumbpiece of the firing-mechanism. Some of the shots took effect, for the Fokker, in spite of the frantic efforts of the pilot to keep it under control, began to dive.

Athol ceased firing. The hostile aircraft was done for. Humanity urged him to let the Hun crew save themselves if it were possible to avoid being dashed to pieces upon the ground.

Erratically swaying, lurching and side-slipping, with one of the wings twisted like a broken reed, the German aircraft fell through a thousand feet of space before the pilot was able to check its descent. For ten seconds it seemed on the point of recovering itself, then the headlong flight was resumed.

Well in its wake followed the British battleplane. Blake was resolved to watch developments. He was curious to know the fate of the Hun crew.

Retarding the battleplane's flight the pilot kept her well under control, circling around the path of his defeated antagonist. Just as the Fokker was on the point of landing with an appalling crash the machine tilted acutely, then making a tail-dive alighted heavily upon the ground, throwing both pilot and observer from their seats.

In an instant the redoubtable Hun pilot regained his feet. Although fully expectant to be greeted by a discharge from the battleplane's machine-gun he staggered towards the wreckage and dragged his unconscious comrade further from the pile of tangled and twisted metal and canvas. Then striking a match and igniting his celluloid map he threw the blazing fabric into the petrol-soaked wreckage.