ARTESIAN WELLS IN THE DESERT. 483 
effect, we must rank the sudden transition from the shady and 
verdant oasis of the desert to the bare and burning party-col- 
ored ocean of sand and rock which surrounds it.* The most 
sanguine believer in indefinite human progress hardly expects 
that man’s cunning will accomplish the universal fulfilment of 
the prophecy, “ the desert shall blossom as the rose,” in its literal 
sense ; but sober geographers have thought the future conversion 
of the sand plains of Northern Africa into fruitful gardens, by 
means of artesian wells, not an improbable expectation. They 
have gone farther, and argued that, if the soil were covered 
with fields and forests, vegetation would call down moisture 
* The variety of hues and tones in the local color of the desert is, I think, 
one of the phenomena which most surprise and interest a stranger to those 
regions. In England and the United States, rock is so generally covered with 
moss or earth, and earth with vegetation, that untravelled Englishmen and 
Americans are not very familiar with naked rock as a conspicuous element of 
landscape. Hence, in their conception of a bare cliff or precipice, they 
hardly ascribe definite color to it, but depict it to their imagination as wear- 
ing a neutral tint not assimilable to any of the hues with which nature tinges 
her atmospheric or paints her organic creations. There are certainly exten- 
sive desert ranges, chiefly limestone formations, where the surface is either 
white, or has weathered down to a dull uniformity of tone which can hardly 
be called color at all; and there are sand plains and drifting hills of weari- 
some monotony of tint. But the chemistry of the air, though it may tame 
the glitter of the limestone to a dusky gray, brings out the green and brown 
and purple of the igneous rocks, and the white and red and blue and violet 
and yellow of the sandstone. Many a cliff in Arabia Petreea is as manifold in 
color as the rainbow, and the veins are so variable in thickness and inclination, 
so contorted and involved in arrangement, as to bewilder the eye of the spec- 
tator like a disk of party-colored glass in rapid evolution. 
In the narrower wadies the mirage is not common; but on broad expanses, 
as at many points between Cairoand Suez, and in Wadi el Araba, it mocks 
you with lakes and land-locked bays, studded with islands and fringed with 
trees, all painted with an illusory truth of representation absolutely indis- 
tinguishable from the reality. The checkered earth, too, is canopied with a 
heaven as variegated as itself. You see, high up in the sky, rosy clouds at 
noonday, colored probably by reflection from the ruddy mountains, while 
near the horizon float cumuli of a transparent, ethereal blue, seemingly balled 
up out of the clear cerulean substance of the firmament, and detached from 
the heavenly vault, not by color or consistence, but solely by the light and 
shade of their salient and retreating outlines. ; 
