"What's that for?" asked Miss Peddensen.

"We cannot allow anyone except naval officers to see how our diving
apparatus is worked", replied Jack. "Some of you step into the
staterooms, on either side, please. All of the visitors must be aft
of this curtain."

The extreme after end of the cabin had been rigged with a heavy curtain
that could be dropped into place.

"Why, I feel as if we were all being penned up here and held for the
slaughter," gasped one American girl, in a tone of fright.

"Yes, indeed!" protested Miss Peddensen. "This is going too far."

"It strikes me as being a good deal like an outrage," blurted the
young Englishman. "Mr. Kimball, can't you--won't you interfere in
this matter?"

"I am very sorry," replied the lieutenant commander, "but I cannot.
This step is necessary, in order to prevent anyone from having an
improper view of the working of the craft. I am going behind the
curtain with you. Mr. Featherstone will remain out in the cabin to
aid in the handling of the boat. You need none of you feel any
uneasiness."

Both Miss Peddensen and the Englishman ceased their objections. But
Jack, remembering the glance that had passed between the pair on deck,
remained behind the curtain, too, as he dropped it.