which the rising and the setting sun paints unbelievable
colors. Here and there thin growths of cottonwood outline thin ribbons
of rivers, few and far between. Here and there alkali whitens the edges
of stained hollows where water lies awhile after spring cloudbursts.
Here and there are salt ponds with no outlet. Yet even in the desolation
of its tawny monotony it has a fascination which is insistent and
cumulative.

But the southwest is not all desert. There are great areas of thin
grazing ranges and lands where dry farming yields fair crops. There are
valleys which produce fruits and grains in abundance. There are hamlets
and villages and cities which are among the oldest in America, centres
of fertile tracts surrounded by deserts which need only water to become
the richest lands on the continent. There are regions reclaimed by
irrigation where farming has brought prosperity. In other places the
plateau covers itself for hundreds of square miles with scrubby pine and
cedar.

All in all, it is a land of rare charm and infinite variety.

To appreciate a region which more and more will enter into American
consciousness and divide travel with the mountains, the reader should
know something of its structural history.

The southwestern part of the United States rose above sea-level and sank
below it many times during the many thousands of centuries preceding its
present state, which is that of a sandy and generally desert plateau,
five to ten thousand feet in altitude. How many times it repeated the
cycle is not fully known. Some portions of it doubtless were submerged
oftener than others. Some were lifting while others were lowering. And,
meantime, mountains rose and were carried away by erosion to give place
to other mountains which also wore away; river systems formed and
disappeared, lakes and inland seas existed and ceased to exist. The
history of our southwest would have been tempestuous indeed had it been
compassed within say the life of one man; but, spread over a period of
time inconceivable to man, there may have been no time when it might
have seemed to be more active in change than its still hot deserts seem
to-day to the traveller in passing trains.

Other parts of the continent, no doubt, have undergone as many changes;
our southwest is not singular in that. But nowhere else, perhaps, has
the change left evidences so plain and so interesting to the
unscientific observer. The page of earth's history is mor