Page 19 - 1915, Springs of CA.

NATURAL WATEES. 19

Bromide and iodide radicles are found in a few spring waters. They
are usually present in saline waters that obtain their mineral contents
from marine deposits but seldom in great proportion.
Ammonium and nitrate radicles are usually supposed to be derived
directly from organic matter and therefore to indicate pollution, but
they may be derived from salts produced by organic matter and hence
may not be evidence of direct contamination. They are seldom
present in mineral spring waters, as these usually issue from uncon-
taminated rock sources.
Phosphate radicle is uncommon in spring water, but it may be taken
into solution from phosphate minerals, such as apatite.
Borate is also an uncommon constituent in water, but some springs
contain it in large amount. It is usually accompanied by sodium and
is probably derived from the solution of borax.
Boric acid is commonly present in volcanic emanations in many
parts of the world, and as boron is a rare constituent of rock-forming
minerals, the presence in areas of volcanic rocks of waters containing
borate is worthy of especial note in connection with mineral springs.1
Arsenate is a rare constituent of water, though there are many
so-called "poison" springs that are popularly believed to contain it.
It is seldom present in measurable proportion, but the water of Owens
Lake, in California, contains 83.8 parts per million 2 of the element
arsenic. (See p. 304.) This is one of the largest amounts reported in a
natural water, but it is in a water that contains more than 213,000
parts of solids per million; so if this water were diluted to a more
nearly normal strength, of, say, 2,000 parts of solids per million, there
would be less than one part per million of arsenic.
The source of carbon dioxide, the gas of the "soda-fountain"
beverages, which is also a common dissolved gas in natural waters,
has been the cause of much discussion. In many lava regions there
are strongly carbonated springs, and the source of their content of gas
is plausibly considered to be carbon dioxide that is occluded in the
underlying rocks, for this gas is known to be one of the prominent
constituents of the vapors that are given off by volcanoes during
eruption. The source of carbon dioxide has been treated fully by
Delkeskamp,3 whose writings have been reviewed by Lindgren.4
Delkeskamp believes that to some extent the carbon dioxide may be
derived from inclusions of liquid carbon dioxide in the quartz grains
of granite and porphyries and be set free by crushing or heat. It is
also probably generated in some places from limestone (calcium car-
1 See Gale, H. S., The origin of colemanite deposits: U. S. Geol. Survey Prof. Paper 85, pp. 3-9,1913.
2 Stone, C. H., and Eaton, P. M., A new analysis of the water of Owens Lake, California: Am. Chem. Soc.
Jour., vol. 28, No. 10, pp. 1164-1170,1906.
3 Delkeskamp, Rudolph, Juvenile and vadose springs: Balneol. Zeitung, vol. 16, No. 5, Feb., 1905. Also
other papers by the same author.
* Lindgren, Waldemar, Econ. Geology, vol. 1, No. 6, pp. 602-612,1906.