The fresh air pouring into his lungs was so different from the corruption of the trenches that he seemed to be raised upon wings.
He resumed his walk toward the hills, and ate breakfast from his knapsack as he went along.

Presently he noticed a large aeroplane circling over his head, and he felt sure that it was observing him.

It was bound to be French or other French machines would attack it, and, after one glance, he walked slowly on.

The machine followed him.

He did not look up again, but he saw a great shadow on the snow that moved with his.
The knowledge that he was being watched and followed even by one of his own army was uncomfortable, and he felt a sensation of relief when he heard a swish and a swoop and the aeroplane alighted on the snow beside him.