"I haven't enough petrol yet. The tank still leaks, though not so badly, and if we shoot, the Turks will swarm up before I can fill up and get away. I think I had better go on with the job, let him come up, and trust to luck."

Keeping his back to the pseudo-Greek, Burton carried another tin to the seaplane. Before he had emptied it into the tank the spy came within hailing distance and let out a jovial greeting in German. No doubt he had recognised the German airman's cap, and, without misgiving, hailed his supposed compatriot.

"Good-morning, my friend," he shouted. "I congratulate you. Another German victory!"

Burton, his back still towards the spy, finished pouring out the petrol, and placed the tin on the ground. As he straightened himself he discreetly drew his revolver and suddenly turned round. The spy was now within half a dozen paces of him.

"Thank you, Mr. Christopoulos," he said. "Another victory--but not a German victory. We shall presently see who is to be congratulated. Meanwhile, you will dismount."

The German, who had reined up at the first glance at Burton's face, turned a sickly colour and half-opened his mouth as if to shout.

"Silence!" cried Burton peremptorily. "If you make the slightest sound I will shoot you on the spot."

He held his revolver carelessly in his left hand, not pointing it at the German lest any of the Turks should come within view. The spy showed more alacrity than skill in dismounting. He clumsily clambered from his saddle, without daring to turn his head in the direction of the Turks, who could now be heard calling to one another beyond the knoll. Burton went up to him.

NONPLUSSED