His hair lifted a little, and a thrill ran down his spine.
He still looked up as he walked along, and there was the sleek shape again! It had come back out of the white mist, and was circling over the German planes, flying with the speed and certainty of an eagle.

He saw three of the German machines whirl about and begin to mount as if they would examine the stranger.

But the solitary plane began to rise again in a series of dazzling circles.

Up, up it went, as if it would penetrate the last and thinnest layer of air, until it reached the dark and empty void beyond.
The _Arrow_--he was sure it could be no other--was quickly lost in the infinite heights, and then the German planes were lost, too, but they soon came back, although the _Arrow_ did not.

It had probably returned to some point over the French line or had gone eastward beyond the Germans.
John felt that he had again seen a sign.