Several minutes later, Del Mar, alone, emerged from the water just outside the submarine harbor and took off his helmet.

He made his way over the rocks, carrying the bomb, until he came to a little fissure in the rocks, like a cavern.  There he hid the bomb carefully.  Still carrying the helmet, he hurried along until he came to the cave entrance that led to the secret passage to the panel in his bungalow library.  Up through the secret passage he went, reaching the panel and opening it by a spring.

In the library Del Mar changed his wet clothes and hid them, then set to work on an accumulation of papers on his desk.

. . . . . . .

That afternoon, Elaine decided to go for a little ride through the country in her runabout.

As she started to leave her room, dressed for the trip, it was as though a premonition of danger came to her.  She paused, then turned back and took from the drawer the searchlight gun which had been sent to her.  She slipped it into the pocket of her skirt and went out.

Off she drove at a fast clip, thoroughly enjoying the ride until, near a bend in the road, as it swept down toward the shore, she stopped and got out, attracted by some wild flowers.  They grew in such profusion that it seemed no time before she had a bunch of them.  On she wandered, down to the rocks, watching the restless waters of the Sound.  Finally she found herself walking alone along the shore, one arm full of flowers, while with her free hand she amused herself by skimming flat stones over the water.

As she turned to pick up one, her eye caught something in the rocks and she stared at it.  There in a crevice, as though it had been hidden, was a strange square package.  She reached down and picked it up.  What could it be?

While she was examining it, back of her, another of those strange be-helmeted figures came up out of the water.  It watched her for an instant, then sank back into the water again.

Elaine, holding the package in her hand, walked up the shore, oblivious to the strange eye that had been fixed on her.

“I must show this to Lieutenant Woodward,” she said to herself.

In the car she placed the package, then jumped in herself carefully and started off.

A moment after she had gone, the diver reappeared, looking about cautiously.  This time the coast was clear and he came all the way out, taking off his helmet and placed it in the secret hiding-place which Del Mar and his men used.  Then, with another glance, now of anger, in the direction of Elaine, he hurried up the shore.

Meanwhile, as fast as her light runabout would carry her, Elaine whizzed over to Fort Dale.

As she entered the grounds, the sentry saluted her, though that part of the formalities of admission was purely perfunctory, for every one at the Fort knew her now.

“Is Lieutenant Woodward in?” she inquired.