, and
as motionless as the surface of a mirror. Nothing stirred its placid
surface, not a ripple, not an insect, not a leaf floating.

Brown had lugged the pneumatic raft down to the shore where he was now
pumping it full: I followed with the paddles, pole, and hydroscope. When
the raft had been pumped up and was afloat, we carried the reel of
gossamer piano-wire aboard, followed it, pushed off, and paddled quietly
through the level cobwebs of mist toward the centre of the lake. From
the shore I heard a gruesome noise. It originated under one of the row of
tents of the heavy artillery. Medusa, snoring, was an awesome sound in
that wilderness and solitude of dawn.

I was unscrewing the centre-plug from the raft and screwing into the
empty socket the lens of the hydroscope and attaching the battery, while
Brown started his sounding; and I was still busy when an exclamation from
my companion started me:

"We're breaking some records! Do you know it, Smith?"

"Where is the lead?"

"Three hundred fathoms and still running!"

"Nonsense!"

"Look at it yourself! It goes on unreeling: I've put the drag on. Hurry
and adjust the hydroscope!"

I sighted the powerful instrument for two thousand feet, altering it from
minute to minute as Brown excitedly announced the amazing depth of the
lake. When he called out four thousand feet, I stared at him.

"There's something wrong--" I began.

"There's _nothing_ wrong!" he interrupted. "Four thousand five hundred!
Five thousand! Five thousand five hundred--"

"Are you squatting there and trying to tell me that this lake is over a
mile deep!"

"Look for yourself!" he said in an unsteady voice. "Here is the tape! You
can read, can't you? Six thousand feet--and running evenly. Six thousand
five hundred!... Seven thousand! Seven thousand five--"

"It _can't_ be!" I protested.

But it was true. Astounded, I continued to adjust the hydroscope to a
range incredible, turning the screw to focus at a mile and a half, at two
miles, at two and a quarter, a half, three-quarters, three miles, three
miles and a quarter--click!

"Good Heavens!" he whispered. "This lake is three miles and a quarter
deep!"

Mechanically I set the lachet, screwed the hood firm, drew out the black
eye-mask, locked it, then, kneeling on the raft I rested my face in the
mask, felt for the lever, and switched on the electric light.

Quicker than thought the solid lance of dazzling light plunged down
through