and feebly and with fumbling fingers placed nuts on the bolts. His hands
wandered uncertainly toward the valves and closed the upper one. He
waved his hand toward Carnes and sank in a heap on the floor of the
lock.

* * * * *

With trembling hands Carnes connected the air and opened the valve. Air
flowed into the lock and the water was gradually forced out. When the
lock was empty, he waited for Dr. Bird to close the outer valve but the
Doctor did not move. Carnes tore at the bolts which held the inner door
and threw his weight against it. It held against his assault, and he
thought frantically. An inspiration came to him, and he disconnected
the air valve. With a whistling rush, the air from the lock rushed into
the sphere and he forced open the inner door. A stream of sea water
drove against his feet through the open valve, and he reached for the
valve to close it. The force of the water held it open for a moment, but
he threw every ounce of his strength into the effort. The valve slowly
closed.

It was beyond his strength to haul the heavy Doctor with his pressure
diving suit through the restricted confines of the inner door, so Carnes
wormed his way into the lock and with trembling fingers unscrewed the
helmet of the Doctor's diving suit. The helmet clanged to the floor and
Carnes scooped up his hands full of water and dashed it into the
Doctor's face. There was no response and he was at his wit's end. He
sprang for the radio to order the sphere hauled up when his glance fell
on the oxygen tank. It took him only a moment to connect a rubber hose
to the tank, and in a few seconds a blast of the life-giving gas was
blowing into the scientist's face. Dr. Bird gave a convulsive gasp or
two and opened his eyes.

"Shut off the juice, Carnes," he said faintly. "Too much of that's
bad."

Carnes shut off the oxygen and Dr. Bird struggled to a sitting position
and inhaled deep breaths.

"That was a narrow squeak, old dear," he said faintly. "Give me a hand
and I'll climb in."

* * * * *

With the detective's aid he climbed into the sphere and Carnes fastened
the inner door. Slowly the Doctor rid himself of the diving suit and lay
prone on the floor, his breath still coming in gasps.

"Thanks for your warning about the time, Carnes," he said. "I knew that
my air supply was running short but I was caught down there and couldn't
readily free myself. I thou