the ice in summer is about thawing-point, but
gradually as the winter cold comes on, it, of course, falls rapidly
on the surface, whence the cold slowly penetrates deeper and deeper
down towards the lower surface, where it naturally keeps at an even
temperature with the underlying water. Observations of the temperature
of the ice in its different layers were constantly taken in order to
ascertain how quickly this cooling-down process of the ice took place
during the winter, and also how the temperature rose again towards
spring. The lowest temperature of the ice occurred in March and the
beginning of April, when at 1.2 metres it was about 3.2 deg. Fahr. (-16 deg.
C), and at 0.8 metre about 22 deg. Fahr. below zero (-30 deg. C). After the
beginning of April it began to rise slowly.

At these low temperatures the ice became very hard and brittle, and was
readily cracked or broken up by a blow or by packing. In the summer,
on the other hand, when its temperature was near melting-point, the
ice became tough and plastic, and was not so readily broken up under
packing. This difference between the condition of the ice in summer
and winter was apparent also to the ear, as the ice-packing in winter
was always accompanied by the frequently mentioned loud noises,
while the packing of the tough summer ice was almost noiseless,
so that the most violent convulsions might take place close to us
without our noticing them.

In the immediate vicinity of the Fram the ice remained perfectly at
rest the whole year through, and she was not at this time exposed to
any great amount of pressure; she lay safe and secure on the ice-floe
to which she was firmly frozen; and gradually, as the surface of the
ice thawed under the summer sun, she rose up higher and higher. In
the autumn she again began to sink a little, either because the ice
gave way under her weight, or because it melted somewhat on the under
surface, so that it no longer had so much buoyancy as before.

Meanwhile, life on board went on in its usual way. Now that we had
daylight, there was of course more work of various descriptions on the
ice than had been the case during the winter. I have already alluded
more than once to our unsuccessful endeavors to reach the bottom by
sounding. Unfortunately we were not prepared for such great depths,
and had not brought any deep-sea sounding apparatus with us. We
had, therefore, to do the best we could under the circumstances,
and that was