On the 5th June we advanced to about seventeen thousand five hundred feet right up the middle of the glacier. As we rose that morning slowly out of the flat in which our tent was pitched and began to climb the steep serac, clouds that had been gathering below swept rapidly up into the Grand Basin, and others swept as rapidly over the summits and down upon us. In a few moments we were in a dense smother of vapor with nothing visible a couple of hundred yards away. Then the temperature dropped, and soon snow was falling which increased to a heavy snow-storm that raged an hour. We made our camp and ate our lunch, and by that time the smother of vapor passed, the sun came out hot again, and we were all simultaneously overtaken with a deep drowsiness and slept. Then out into the glare again, to go down and bring up the remainder of the stuff, we went, and that night we were established in our last camp but one. We had decided to go up at least five hundred feet farther that we might have the less to climb when we made our final attack upon the peak. So when we returned with the loads from below we did not stop at camp, but carried them forward and cached them against to-morrow's final move. [Illustration: Third camp in the Grand Basin--17,000 feet, showing the shattering of the glacier walls by the earthquake. The rocks at the top of the picture are about 19,000 feet high and are the highest rocks on the south peak of the mountain.] [Sidenote: Last Camp] On Friday, the 6th June, we made our last move and pitched our tent in a flat near the base of the ridge, just below the final rise in the glacier of the Grand Basin, at about eighteen thousand feet, and we were able to congratulate one another on making the highest camp ever made in North America. I set up and read the mercurial barometer, and when corrected for its own temperature it stood at 15.061. The boiling-point thermometer registered 180.5, as the point at which water boiled, with an air temperature of 35 deg. It took one hour to boil the rice for supper. The aneroids stood at 14.8 and 14.9, still steadily losing on the mercurial barometer. I think that a rough altitude gauge could be calculated from the time rice takes to boil--at least as reliable as an aneroid barometer. At the Parker Pass it took fifty minutes; here it took sixty. This is about the height of perpetual snow on the great Himalayan peaks; but we had been above the perpetual snow-line for forty-eight days.