94 FieLp CoLumpian MuseEuM—GEoLocy, VOL. I. 
result is that the surface of the snow field is cut into numberless, rough, 
wedge-shaped teeth. Over these, progress is very slow and difficult. 
The snow is rarely more than a few feet in depth, a fact to be accounted 
for by the regular slope of the cone and the permeability and dark color 
of the ash bed on which the snow lies. The ashes, retaining heat, melt 
the snow and drain away the water constantly from the under surface 
of the snowfield. In depressions, the snow accumulates to a greater 
depth, but never to an amount that would make the formation of a 
glacier possible. The nearest approach to this is found at the foot 
of the Pico del Fraile, where the snow presents something of the 
character of a glacier.* Nothing like crevasses occur in the snow, 
and the yawning chasms reported by travelers, or would-be travelers, 
can be set downas purelyimaginary. Besides the difficulty of ascend- 
ing over so rough and steep a surface, other difficulties of the ascent 
are the cold, which is, of course, of varying degree, but has been 
sufficient to freeze the feet of tourists; the fierce wind produced by 
the descent of the air which has been chilled by the cold slopes of the 
mountain,and the excessive fatigue caused by the fact that the heart and 
lungs are compelled to work at about twice their normal speed in order 
to gain from the rarefied air sufficient oxygen for the system. These 
difficulties may well be considered before an attempt to ascend is made, 
but if the system is sufficiently strong to endure these hardships no 
other danger need be feared. 
It was about 11 4. M., after four hours of toilsome climb on foot, 
that the first suggestion of the proximity of the crater came in the 
form of a strong odor of hydrogen-sulphide which filled the air. A 
little later the guide in front shouted: ‘‘ Z/egamos!’ (We are there), 
and we came out upon a ridge of ashes whence we could look into the 
yawning depths of the crater below. 
Let one imagine a pit about 2,000 feet in its greater diameter, 
t,300 1n its lesser, and from 800 to 1,500 feet in depth, let down into 
the summit of the mountain, from different points in the nearly per- 
pendicular walls of which jets of steam come hissing and sizzling, 
and rocks of varying size continually fall from the walls of the crater 
and plunge witha roar to the bottom; imagine that the bottom is 
heaped unevenly with debris of various sorts and colors, and that all 
this must be observed in a wind so fierce that it causes the very walls 
of the crater to tremble, and one gets a good idea of the first impres- 
sion made upon the observer by the crater. 
There is nothing of the heat and movement which might be 
expected from being at the point of issue of the volcanic forces, for, 
*Aguilera and Ordofiez, of. cit. p. 18. 
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