Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean: Vol. 5, Pt. 2

TIMBER-THERMAL SPRINGS-INCRUSTATIONS.
This is a favorable place for the culture of the grape, and for many of the tropical fruits; it
will, doubtless, soon become noted for the excellence and variety of its productions. The cold
summit of the peak of San Bernardino, upon which snow rests for the greater part of the year,
has a great influence on the climate of the valley, and moderates its temperature during the
night by the cool currents of air which descend from it.
In the Bernardino Sierra, especially in the canions and ravines near the summit, and between
the Cajon Pass and the peak of San Bernardino, there is abundance of pine and spruce timber,
which was being cut and sawed into lumber by the Mormons for their own use, and for sale at
Los Angeles. The brooks which flow through the ravines furnish good water-power, and
several saw mills have been erected high up in the mountains. These supply San Bernardino
with lumber, and furnish a large surplus, which is carried to Los Angeles for sale. A good
road has been made from these mills to the settlement at great expense, and a large quantity of
lumber is brought down and taken to market. When the railroad is constructed from the
mouth of the Gila to this valley, and beyond it to Los Angeles, a large part of the timber for
ties can be obtained from these forests, cheaper than it can be procured from Oregon.
Hot springs.-Around the borders of the valley there are numerous localities of thermal
springs. The warm and hot waters gush out from the granitic rocks on the flanks of San
Bernardino and the adjacent heights. In one place the springs are so numerous, and the water
rises in such volume, that a good sized mill-stream of hot water is formed, which flows down
into the valley and is one of the principal tributaries of the Santa Anna river. This brook of
hot water retains a temperature of 1000 three or four miles from its source.
I visited several of the springs on the side of the Sierra, between. San Bernardino mountain and
the Cajon Pass, near the saw mill road, and found them to rise through an accumulation of
drift and debris, along the banks of a small mountain brook. It was evident that the subjacent
granite was very near the surface, as shown by one or two outcrops, from one of which the hot
water issued. Small springs rise at intervals of ten to twenty feet, along a distance of thirty
or forty rods. Their waters unite and form a little stream that empties into the brook, a short
distance below. The banks of these streams were thickly overgrown with grass. A dense
mass of beautiful green conferve grew from the bottom and sides of the channel, and floated in
rich, waving masses in the hot water. In the immediate vicinity of the springs, however, no
vegetable growth was visible. The rocks and gravel, in contact with the water, were covered
with a snow-white incrustation; and little twigs and leaves that had fallen into it were
softened to a white pulpy mass, and were partly incrusted. This was also the case with insects
that were lying dead in the shallows of one of the springs; but I could not observe that, in
either case, any petrifaction or internal deposition of mineral matter had taken place.
The following temperatures of different springs were observed: 172~, 1690, 1660, 1300, 1280,
108~ Fahrenheit. The temperature of the hot stream, below all the springs, was found to be
130~, and the mountain brook only 65~. Temperature of the air, 76~.
The variation in the temperature of the springs is undoubtedly caused by the different circumstances under which the water reaches the surface. Some of them boil up among a mass of
granite boulders and gravel, and others run out from the side of a bank of loose detritus or drift
overlying the granite.
The white crust was not found in equal quantities at all of the springs. It appeared to be
most abundant at one of them. It adhered very closely to the rocks, and formed little projecting points or blunt protuberances from their surfaces. Some of the pebbles lying in the stream
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