Our instruments for determining altitude consisted Page 21of a special mountain-mercurial barometer made by Mr. Henry J. Green, of Brooklyn, capable of recording only such air pressures as one might expect to find above 12,000 feet; a hypsometer loaned us by the Department of Terrestrial Magnetism of the Carnegie Institution of Washington, with thermometers especially made for us by Green; a large mercurial barometer, borrowed from the Harvard Observatory, which, notwithstanding its rough treatment by Mr. Hinckley's mule, was still doing good service; and one of Green's sling psychrometers. Our most serious want was an aneroid, in case the fragile mercurials should get broken. Six months previously I had written to J. Hicks, the celebrated instrument maker of London, asking him to construct, with special care, two large “Watkins” aneroids capable of recording altitudes five thousand feet higher than Coropuna was supposed to be. His reply had never reached me, nor did any one in Arequipa know anything about the barometers. Apparently my letter had miscarried. It was not until we opened our specially ordered “mountain grub” boxes here in Chuquibamba that we found, alongside of the pemmican and self-heating tins of stew which had been packed for us in London by Grace Brothers, the two precious aneroids, each as large as a big alarm clock. With these two new aneroids, made with a wide margin of safety, we felt satisfied that, once at the summit, we should know whether there was a chance that Bandelier was right and this was indeed the top of America.
Page 22For exact measurements we depended on Topographer Hendriksen, who was due to triangulate Coropuna in the course of his survey along the 73d meridian. My chief excuse for going up the mountain was to erect a signal at or near the top which Hendriksen could use as a station in order to make his triangulation more exact. My real object, it must be confessed, was to enjoy the satisfaction, which all Alpinists feel, of conquering a “virgin peak.” Page 23
[1] A league, usually about 3⅓ miles, is really the distance an average mule can walk in an hour.
Chapter II
Climbing Coropuna
The desert plateau above Chuquibamba is nearly 2500 feet higher than the town, and it was nine o'clock on the morning of October 10th before we got out of the valley. Thereafter Coropuna was always in sight, and as we slowly approached it we studied it with care. The plateau has an elevation of over 15,000 feet, yet the mountain stood out conspicuously above it. Coropuna is really a range about twenty miles long. Its gigantic massif was covered with snow fields from one end to the other. So deep did the fresh snow lie that it was generally impossible to see where snow fields ended and glaciers began. We could see that of the five well-defined peaks the middle one was probably the lowest. The two next highest are at the right, or eastern, end of the massif. The culminating truncated dome at the western end, with its smooth, uneroded sides, apparently belonged to a later volcanic period than the rest of the mountain. It seemed to be the highest peak of all. To reach it did not appear to be difficult. Rock-covered slopes ran directly up to the snow. Snow fields, without many rock-falls, appeared to culminate in a saddle at the base of the great snowy dome. The eastern slope of the dome itself offered an unbroken, if steep, path to the top. If we could once reach the snow line, it looked as Page 24though, with the aid of ice-creepers or snowshoes, we could climb the mountain without serious trouble.
Mt. Coropuna from the South