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Arrangements were made with Captain Michel of the Signal Corps at Fort
Gibbon, when the expedition started to the mountain in March, 1913, to
read the barometer at that post three times a day and record the reading
with the reading of the attached thermometer. Acknowledgment is here
made of Captain Michel's courtesy and kindness in this essential
co-operation. The reading at Fort Gibbon which most nearly synchronizes
with the reading on top of the mountain is the one taken at noon on the
7th June. The reading on top of the mountain was made at about 1.50
P. M., so that there was an hour and fifty minutes difference in time.
The weather, however, was set fair, without a cloud in the sky, and had
been for more than twelve hours before and remained so for thirty-six
hours afterward. It would seem, therefore, that the difference in time
is negligible. The reading at Fort Gibbon, a place of an altitude of
three hundred and thirty-four feet above sea-level, at noon on the 7th
June, was 29.590 inches with an attached thermometer reading 76.5 deg. F.
The reading on the summit of Denali, at 1.50 P. M. on the same day, was
13.617. The writer is greatly chagrined that he cannot give with the
same confidence the reading of the attached thermometer on top of the
mountain, but desires to set forth the circumstances and give the
readings in his note-book records.

The note-book gives the air temperature on the summit as 7 deg. F., taken
by a standard alcohol minimum thermometer, and it remained constant during
the hour and a half we were there. The sun was shining, but a bitter
north wind was blowing. But the reading of the thermometer attached to
the barometer is recorded as 20 deg. F. I am unable to account for this
discrepancy of 13 deg. The mercurial barometer was swung on its tripod
inside the instrument tent we had carried to the summit, a rough zero
was established, and it was left for twenty minutes or so to adjust
itself to conditions before an exact reading was taken. It was my custom
throughout the ascent to read and record the thermometer immediately
after the barometer was read, but it is almost certain that on this
momentous occasion it was not done. Possibly the thermometer was read
immediately the instrument was taken out of its leather case and its
wooden case and set up, while it yet retained some of the animal heat of
the back that had borne it, and the reading was written in the prepared
place. Then when the b