To this end careful arrangements were made and much labor and trouble undergone. The author carried his standard mercurial mountain barometer to Fort Gibbon on the Yukon in September, 1912, and compared it with the instrument belonging to the Signal Corps of the United States army at that post. A very close agreement was found in the two instruments; the reading of the one, by himself, and of the other, by the sergeant whose regular duty it was to read and record the instrument, being identical to two places of decimals at the same temperature.
Readings on the Summit
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° 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° 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° F. I am unable to account for this discrepancy of 13°. 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 barometer was finally read, no temperature of the attached thermometer was noted. This is the only possible explanation that occurs, and it is very unsatisfactory. It was not until we were down at the base camp again that I looked at the figures, and discovered their difference, and I could not then recall in detail the precise operations on the summit. It is hard to understand, ordinarily, how any man could have recorded the two readings on the same page of the book without noticing their discrepancy, but perhaps the excitement and difficulty of the situation combined to produce what Sir Martin Conway calls “high altitude stupidity.”
In Exculpation
It is indeed impossible to convey to the reader who has never found himself circumstanced as we were an understanding of our perturbation of mind and body upon reaching the summit of the mountain: breathless with excitement—and with the altitude—hearts afire and feet nigh frozen. What should be done on top, what first, what next, had been carefully planned and even rehearsed, but we were none of us schooled in stoical self-repression to command our emotions completely. Here was the crown of nearly three months’ toil—and of all those long years of desire and expectation. It was hard to gather one’s wits and resolutely address them to prearranged tasks; hard to secure a sufficient detachment of mind for careful and accurate observations. The sudden outspreading of the great mass of Denali’s Wife immediately below us and in front of us was of itself a surprise that was dramatic and disconcerting; a splendid vision from which it was difficult to withdraw the eyes. We knew, of course, the companion peak was there, but had forgotten all about her, having had no slightest glimpse of her on the whole ascent until at the one stroke she stood completely revealed. Not more dazzling to the eyes of the pasha in the picture was the form of the lovely woman when the slave throws off the draperies that veiled her from head to foot. Moreover, problems that had been discussed and disputed, questions about the conformation of the mountain and the possibilities of approach to it, were now soluble at a glance and clamored for solution. We held them back and fell at once to our scientific work, denying any gratification of sight until these tasks were performed, yet it is plain that I at least was not proof against the disturbing consciousness of the wonders that waited.
It was bitterly cold, yet my fingers, though numb, were usable when I reached the top; it was in exposing them to manipulate the hypsometrical instruments that they lost all feeling and came nigh freezing. And breathlessness was naturally at its worst; I remember that even the exertion of rising from the prone position it was necessary to assume to read the barometer brought on a fit of panting.
Calculations for Altitude
With these circumstances in mind we will resume the discussion of the readings taken on the summit and their bearing upon the altitude of the mountain. It seems right to disregard the temperature recorded for the attached thermometer, and to use the air temperature, of which there is no doubt, in correcting the barometric reading. So they stand:
| Bar. | Temp. |
| 13.617 inches | 7° F. |