the base of the peak earn© swirling up about the summit and the wind 
blew fiercely, A severe headache that had been with me all the morning 
now began to became especially painful and with it a nausea and feeling 
of general shakiness that made the last part of the ascent very diffi¬ 
cult, Several times I was forced to stop on the steep snowy slope and 
lean heavily on my alpenstock to avoid a dangerous fall due to sheer 
weakness or loss of control of my muscles. This would pass off and I 
would work on a few yards further. 
As I had no trouble of this kind on either of the other peaks, I 
attributed it to the fact that I had been suffering from a severe cold 
for a week previous to this ascent and, in consequence, was in a poor 
physical condition to meet the exertion, 
l 
The men were awaiting me sheltered within the lip of the crater re¬ 
clining on a narrow slope of sand and fine scoriae mixed with small 
fragments of sulphur which descended a few feet below them and then 
dropped into the abyss of the crater. The approach to the crater is 
abrupt so that one is on its verge without warning and the effect is 
rather startling. 
The crater is a huge chasm several times greater than that on Popo- 
catapetl, and much more effective for that reason. It must be 1800 ft, 
deep from the side on which we approached, the southwest,- but is lower 
on the opposite side. It is about 600x500 yards in diameter - its long¬ 
est dimension in an easterly and westerly direction, and is irregular 
in outline, being broken by small bays. The contour of its upper edge 
is also irregular, the highest point on the west side being several 
hundred feet above the eastern wall of the crater. The drop is perpend¬ 
icular from the top down to the talus lying at the bottom. While I was 
at the summit there was a constant dropping of fragments from the high 
walls of the crater,- these making a faint rattling sound as they struck 
