Mr. J.J. Mcgillivray, who has been for many years in the United States
mineral survey service, has some interesting things to say about the
overflow of the Colorado desert, which has excited so much comment,
and about which so many different stories have been told:
"None of the papers, so far as I know," said Mr. McGillivray, "have
described with much accuracy or detail the interesting thing which has
happened in the Colorado desert or have stated how it happened. The
Colorado desert lies a short distance northwest of the upper end of
the Gulf of California, and contains not far from 2,500 square miles.
The Colorado River, which has now flooded it, has been flowing along
to the east of it, emptying into the Gulf of California. The surface
of the desert is almost all level and low, some of it below the sea
level. Some few hundreds of years ago it was a bay making in from the
Gulf of California, and then served as the outlet of the Colorado
River. But the river carried a good deal of sediment, and in time made
a bar, which slowly and surely shut off the sea on the south, leaving
only a narrow channel for the escape of the river, which cut its way
out, probably at some time when it was not carrying much sediment.
Then the current became more rapid and cut its way back into the land,
and, in doing this, did not necessarily choose the lowest place, but
rather the place where the formation of the land was soft and easily
cut away by the action of the water.
"While the river was cutting its way back it was, of course, carrying
more or less sediment, and this was left along the banks, building
them all the time higher, and confining the river more securely in its
bounds. That is the Colorado River as we have known it ever since its
discovery. Meantime, the water left in the shallow lake, cut off from
the flow of the river, gradually evaporated--a thing that would take
but a few years in that country, where the heat is intense and the
humidity very low. That left somewhere about 2,000 miles of desert
land, covered with a deposit of salt from the sea water which had
evaporated, and most of it below the level of the sea. That is the
Colorado desert as it has been known since its discovery.
"Then, last spring, came the overflow which has brought about the
present state of affairs. The river was high and carrying an enormous
amount of sediment in proportion to the quantity of water. This
gradually filled up the bed of the stream and caused it to overflow
its banks, breaking through into the dry lake where it had formerly
flowed. The fact that the water is salt, which excited much comment at
the time the overflow was first discovered, is, of course, due to the
fact that the salt in the sea water which evaporated hundreds of years
ago has remained there all the time, and is now once more in solution.
"The desert will, no doubt, continue to be a lake and the outlet of
the river unless the breaks in the banks of the river are dammed by
artificial means, which seems hardly possible, as the river has been
flowing through the break in the stream 200 feet wide, four feet deep,
and flowing at a velocity of five feet a second.
"It is an interesting fact to note that the military survey made in
1853 went over this ground and predicted the very thing which has now
happened. The flooding of the desert will be a good thing for the
surrounding country, for it does away with a large tract of absolutely
useless land, so barren that it is impossible to raise there what the
man in Texas said they mostly raised in his town, and it will increase
the humidity of the surrounding territory. Nature has done with this
piece of waste land what it has often been proposed to do by private
enterprise or by public appropriation. Congress has often been asked
to make an appropriation for that purpose."
Mr. McGillivray had also some interesting things to say about Death
Valley, which he surveyed.
"It has been called a _terra incognita_ and a place where no human
being could live. Well, it is bad enough, but perhaps not quite so bad
as that. The great trouble is the scarcity of water and the intense
heat. But many prospecting parties go there looking for veins of ore
and to take out borax. The richest borax mines in the world are found
there. The valley is about 75 miles long by 10 miles wide. The lowest
point is near the center, where it is about 150 ft. below the level of
the sea. Just 15 miles west of this central point is Telescope peak,
11,000 ft. above the sea, and 15 miles east is Mt. Le Count, in the
Funeral mountains, 8,000 ft. high. The valley runs almost due north
and south, which is one reason for the extreme heat. The only stream
of water in or near the valley flows into its upper end and forms a
marsh in the bed of the valley. This marsh gives out a horrible odor
of sulphureted hydrogen, the gas which makes a rotten egg so
offensive. Where the water of this stream comes from is not very
definitely known, but in my opinion it comes from Owen's lake, beyond
the Telescope mountains to the west, flowing down into the valley by
some subterranean passage. The same impurities found in the stream are
also found in the lake, where the water is so saturated with salt,
boracic acid, etc., that one can no more sink in it than in the water
of the Great Salt lake; and I found it so saturated that after
swimming in it a little while the skin all over my body was gnawed and
made very sore by the acids. Another reason why I think the water of
the stream enters the valley by some fixed subterranean source is the
fact that, no matter what the season, the flow from the springs that
feed the marsh is always exactly the same.
"The heat there is intense. A man cannot go an hour without water
without becoming insane. While we were surveying there, we had the
same wooden cased thermometer that is used by the signal service. It
was hung in the shade on the side of our shed, with the only stream in
the country flowing directly under it, and it repeatedly registered
130°; and for 48 hours in 1883, when I was surveying there, the
thermometer never once went below 104°."--_Boston Herald._
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