A
fish, a huge, blind fish, its cavernous mouth stretched wide. It came
straight for me, just above. In a second it would leap through. A
scream of terror trembled in my throat. Then it hit the edge of the
translucent green wall--and vanished! Was I dreaming? Had Jim hit me
too hard?

Something stirred in the back of my mind. I sensed dimly that here lay
the explanation of the disappearance of the _New York_, the very
mystery that I had come to solve. Almost I had it; then it slipped
away.

* * * * *

"Here's the doctor!" someone said. There was a little stir of activity
about me. I allowed my eyes to close, as if in utter weariness.

"What's all this? What have you got here?" A gruff voice, intolerant.

"One of our sub-sea scouts, sir. Just come back, after some delay. Her
eye was smashed, and there are grapple marks on her. Must have been
caught, and then slipped away. She was leaking badly. We got her
through the lock just in time." Jim had evidently added a few touches
of his own. "Comrade Pauloff seems to have been seriously injured.
He's got a bad cut on his scalp, and was unconscious till a moment
ago. Opened his eyes just as you came along."

"Hm. Let's see." I felt a none too gentle hand finger my wound. It
throbbed maddeningly. The doctor spoke again. "A nasty crack, but no
fracture. Here, you--wake up." I made no move. "Come on, wake up!" I
heard the plop of a cork being drawn from a bottle; a pungent odor
assailed my nostrils, choked me. I writhed, pulled at the hand holding
the bottle to my nose and opened my eyes.

"That's better. How do you feel now?"

I raised a hand to my injury and muttered, in Russian. "Hurts,
papashka." I kept my expression as blank, as uncomprehending, as I
could.

The doctor flashed an understanding glance at the captain, then turned
back to me. "What's your name?"

Memories of my grandmother's tales of her youth came flooding back to
me. "Pavel, son of Pauloff."

It was the formula of the Russian student, in his teens.

"Your rank?"

"Second year. Petrovski Gymnasium."

The physician turned away. "No use bothering him now. A clear case of
amnesia.

"He's been thrown back to his high school days. I've had a number of
cases like that among your scouts lately." Blessed inspiration! "Only
cure is rest. Get him over to the infirmary. We'll evacuate him to a
base hospital to-morrow."

* * * * *

I wa