With the accession of Don Rodriguez, and his attendants to our party, an excursion to the summit of the Peak was organized. Accordingly on September 8th, two men being left at the station to observe barometer and thermometers every quarter of an hour, all the rest of us,—loaded with meteorological instruments, photographical apparatus and other knickknacks,—started off on foot by break of day.

A few yards beyond our walls, coming to the end of the pumice-stone ground, that furthest limit of horses and mules, we entered the wilderness of the “Malpays,” or those ultimate lava streams of Rambleta, the torrents of black lava rocks and stones. At first the path led up a narrow angular valley, between the flanks of two adjacent ridges. The sides, inclined at a steep angle, were mere loose stones, of which the larger blocks formed the bottom of the channel, and had a little fine yellow pumice sifted in amongst them. This was dust that had been carried up by east winds from the plateau of Alta Vista, and had not travelled far. Step by step the quantity of it decreased, and before long we were walking up the ascending angular passage, on nothing but black disjointed stones.

Presently, large opposing masses, obliged us to make a slight diversion. One of the sailors, who was walking ahead; very zealous, and from having visited the Peak a few days before, anxious to show his knowledge,—went straight up the sloping side, sending down instantly a shower of rolling stones;