"What ship are you?" he shouted.

"The Cotswold, for Hull. Just sighted an enemy submarine and opened fire on her," came the answer.

"A submarine! How long ago?"

"About ten minutes. She was using her machine-gun."

"Why don't you provide your look-outs with spectacles?" answered Lawless wrathfully. "It was me you sighted, not a submarine!"

"I saw her periscope," answered the skipper of the Cotswold.

"Saw your grandmother! You opened fire on me and I replied."

"Then it was your business to hail me. Pity you haven't something better to do than take pot shots at passenger boats," answered the merchant skipper with some heat.

The latter was obviously in the wrong, but, as a matter of fact, during his voyage across the Atlantic he had been chased by two enemy submarines and only by skilful seamanship and unceasing vigilance had succeeded in eluding them and saving his ship. He was, therefore, a trifle "nervy" and apt to suspect every indistinguishable floating object he met of being a submarine. Possibly, seen dimly through the fog, the Knat looked something like a submarine awash and the captain of the Cotswold had been justified in opening fire on her. Lawless, however, was ignorant of this, and the skipper's last taunt made him almost dance with rage. Fortunately, perhaps, another fog bank rolled up at this moment and the two vessels were again hidden from each other.

For some moments Lawless growled to himself things which, had the captain of the Cotswold heard them, might have produced a resumption of hostilities. Suddenly he gave vent to an exclamation: