sacks. One was choked by the fumes, if near the furnaces, and penetrated by the draughts through crevice and broken window-pane, if remote. Tlamaca is itself 12,500 feet above the sea, and its thermometer ranges about 40° Fahrenheit. Without other covering than a light rubber overcoat—for I had not been instructed to bring other—it was impossible to sleep. I went out and the yard, sentry fashion, at three o'clock in the morning, as the only resource for keeping the blood in circulation. It was moonlight, and I had the partial compensation of studying the volcano, bathed in a lovely silver radiance.
Mountains are rather given to making their poorest possible figure. Here we are, at this point, already 12,500 feet above the sea, and this is to be subtracted from the total. Shall we ever meet with a good, honest mountain rising its whole 19,673 feet at once, without these shuffling evasions? I fear not. They are only to be found in the designs of tyro pictorial art.
I say 19,673 feet, because so much General Ochoa insists that Popocatepetl is, by a late measurement with the barometer of Gay-Lussac. He even estimates 1700 feet more for the upper rim of the crater, which has never been scaled. I do not know that this has ever passed into any official form, but I had it from his own lips. The latest Mexican atlas makes it but 5400 metres, or 17,884: feet, which coincides with the measurement of Humboldt. I much prefer to rally to General Ochoa, for my part, and to believe that I have climbed a mountain of 21,373 feet, instead of one of a mere 17,884.
The barometer of our own expedition, unfortunately, stopped at 17,000 feet, the limit for which it was set—a limit which barometers are not often called upon to surpass.
