“What do you mean?” asked Blake.

“Well, I have an idea he’s after our films, the same as he was before, either to spoil them or get them for some purpose of his own.  Just now we aren’t taking any, and he hasn’t any desire, I suppose, to get possession of the unexposed reels.  But when we begin to make pictures of our boys in the trenches, and perhaps of some engagements, we’ll have to see that the reels are well guarded.”

“We will,” agreed Blake.  “What was going on up here?  We heard a racket, and Labenstein rushed up half dressed.”

“Lifeboat spilled—­no harm done,” explained Charlie.  “Well, I might as well take this camera below if we’re not going to use it.”

“Come on, Blake,” urged Joe.  “They’re going to have gun drill.  Let’s watch.”

The vessel carried four quick-firing guns for use against submarines, one each in the bow and stern, and one on either beam.  The gunners were from Uncle Sam’s navy and were expert marksmen, as had been evidenced in practice.

“Are we in the danger zone yet?” asked one of the two young women whose acquaintance Blake and Joe had made through the courtesy of Captain Merceau.

“Oh, yes,” Blake answered.  “We have been for some time.”

“But I thought when we got there we would be protected by warships or torpedo-boat destroyers,” said Miss Hanson.

“We’re supposed to be,” replied Joe.  “I’ve been looking for a sight of one.  They may be along any minute.  Look, there comes a messenger from the wireless room.  He’s going to the bridge where the captain is.  Maybe that’s word from a destroyer now.”

Interestedly they watched the messenger make his way to the bridge with a slip of paper in his hand.  And then, before he could reach it, there came a hail from the lookout in the crow’s nest high above the deck.

He called in French, but Joe and Blake knew what he said.  It was: 

“Periscope ahoy!  Two points off on the port bow!  Periscope ahoy!”

CHAPTER VIII

BEATEN OFF

Decks that, a moment, before, had exhibited scenes of quietness, though there was a nervous tenseness on all sides, at once assumed feverish activity.  Officers on duty, hearing the cry of the lookout, called to him to repeat his message, which he did, with the added information that the submarine, as evidenced by the appearance of the periscope cutting the water, was approaching nearer, and with great swiftness.

“Here she comes, Blake!” cried Joe, as the two boys stood together at the spot from which they had been watching the wireless messenger a moment before.  “Here she comes!  Now for a chance at a picture!”

“You’re not going below, are you?” cried Blake.

“Why not?” asked Joe, pausing on his way to the companionway.

“Why, we may be blown up at any moment!  We may be hit by a torpedo!  I don’t see why they haven’t loosed one at us before this, as their periscope is in sight.  You shouldn’t go below now!  Stay on deck, where you’ll have a chance to get in the boat you’re assigned to!”