The D-16, with her periscope protruding slightly above the water, dashed on at full speed.
CHAPTER XXIII.
THE CHASE.
Lord Hastings stood at the periscope. Frank was on duty in the lookout compartment. Every man was at his post and ready for instant action. Torpedoes were in the tubes and every man stood at attention, for there was no knowing at what moment they might come upon the enemy, and Lord Hastings had no mind to allow the enemy to fire the first shot.
Suddenly, as Frank peered intently into the murky water, a blinding light dazzled his eyes; then, as suddenly, it was gone and all was black before him.
The lad immediately summoned Lord Hastings, to whom he related this strange occurrence. The latter thought some time before replying:
“There is but one possible explanation. There can be no such light beneath the sea except that furnished by the hand of man. The Austrian submarine must have some device similar to ours.”
“There can be no other explanation, sir.”
“And the result is that we shall have to be doubly careful,” said Lord Hastings, as he returned to his post at the periscope.
Suddenly Jack, who stood near Lord Hastings, was startled to see his commander leap back and utter a loud exclamation.
“There she goes!” he cried. “Push her to the limit, Mr. Templeton.”