" he said, "out of the case numbered four, in
the cabin."

I went and fetched the instrument, the men looking as much astounded as
I was myself to see the doctor going coolly to work examining the
structure of the ice, with its curious water-worn face. Then he seemed
to be making measurements, and he ended by coming to us, rubbing his
hands.

"Curious position, isn't it!" he said, laughing. "By the way, captain,
I should cast off those ice-anchors, in case the iceberg should make
another turn. They might be the cause of mischief."

"Cause of mischief! Hark at him!" said Abram. "When we're perched two
hundred foot up here in the air! Come on, lads."

The ice-anchors were taken out of the holes that had been cut for them,
and were got on board as we settled down for the night, no man feeling
disposed to sleep; and all this while we were drifting slowly with the
stream farther and farther south.

This went on for four days, and then, one night, I remember thinking, as
I lay on deck, that could we be sure of the ice melting slowly at the
top, and letting us down, we should be safe; but I knew that the bottom
melted faster in the warm water, then the top grew heavier, and over it
went again.

I tried very hard to keep awake in case of danger; but it was of no use,
for I was worn out with watching, and at last I went off soundly to
sleep, dreaming that I was drowned, and living in an ice cave, fish
fashion, at the bottom of the sea, when I was awakened by Scudds, who
shook me, crying, "Wake up, skipper! she's a-going to launch herself!"

I jumped to my feet, to find the doctor on deck, lecturing his nephew
about the launching of ships, and pointing out the gradual slope down of
the ice valley in which we lay.

"She's shifted two foot!" said Scudds. "I felt her move!"

"Batten down the hatches!" I roared, seeing what was coming; and as
soon as this was done, and the ship made water-tight, I gave fresh
orders for every man to lash himself fast to the shrouds and
belaying-pins, while I myself secured the doctor and his nephew, neither
of them seeing the slightest danger in what was to come.

Hardly had I done this, than there was a strange creaking, scratching
noise, as of iron passing over ice; and then we felt that the vessel was
in motion, gilding down the horrible precipice toward the sea.

At first she moved very slowly, but gathering speed, she glided faster
and faster, till, with a rush like an avalan