59 
from the darker sand and rocks that compose most of the surface, 
and pile this light sand into more or less crescent-shaped hills 
up to perhaps six or eight feet in height and fifty feet or more in 
length ; these advance slowly with the wind as it blows the sand 
on the exposed side over the crest to the sheltered side. These 
hills, moreover, not only stand out clearly defined over the darker 
surface, but they are covered all over the windward side by the 
most delicate tracery of little waves, closely imitating those pro- 
duced on water by a slight breeze and they are so numerous 
that at a little distance the outline of one hill becomes merged 
into that of its neighbors on either side. 
or the use of the railway as well as for the town of Mol- 
lendo, water is brought in pipes the entire distance from Arequipa, 
106 miles, and from this source sufficient is taken to cultivate 
small gardens at the stations, containing bananas, oranges, corn, 
beans, passion flowers, roses, pinks and various other ornamen- 
tal and useful plants, that together produce a delightful contrast 
to the desolate wastes shutting them in. 
As one rises and approaches Arequipa vegetation gradually 
appears again to someextent. Various tall, more or less branch- 
ing cacti are conspicuous, shrubby composites are common and 
various small bushes and grasses appear on the gravelly hillsides 
and ravines. Even a few ferns and mosses are found, but every- 
where the country is too dry for any extensive cultivation with- 
out artificial irrigation and this is carried on quite extensively, 
both in Arequipa and neighboring valleys. The railway on 
leaving Arequipa rises rapidly, winding in and out among the 
bare hills till near the summit of the continental divide, when the 
grade becomes more gradual and one scarcely realizes that he is 
at the highest point at a station called Crucero Alto, 14,666 ft. 
above the sea. Let one attempt the slightest exertion, however, 
and at once the great difference in the air is perceptible by the 
difficulty of breathing, often accompanied by headache and even 
nausea. Vegetation is not uncommon at this attitude, some of 
the best and most abundant grasses thriving at from 12,000 to 
14,000 ft.; various cacti also occur, although what may be termed 
the cactus belt is somewhat lower, from about 6,000 to 10,000 ft. 
