Page 329 - 1915, Springs of CA.

MAGNESIC SPRINGS. 309
and water is pumped from it to supply the water boxes of the lumber
company. The pump is run constantly during working hours and
lifts 30,000 gallons a day, but 5 minutes after pumping is stopped the
well overflows. Much gas rises with the water, and in order to
prevent its interference with pumping the well has been capped and
a 2£-inch pipe extends down the well a considerable distance.
The well is sunk into the alluvium and more consolidated sediments
that border the bay, and its water evidently obtains its saline and
other constituents directly from the marine beds.
MAGNESIC SPRINGS.
SPRINGS PREVIOUSLY DESCRIBED.
Most of the magnesic springs in the State have been described
under headings suggested by other more pronounced characteristics,
but it has been thought advisable to give them brief mention under
one heading. The springs at Duncan (Mendocino 31, p. 167), Howard
(Lake 51, p. 95), Spiers (Lake 52, p. 190), NapaRock (Napa9, p. 161),
and Phillips (Napa 8, p. 161) springs and at The Geysers (Sonoma4,
p. 83), as has already been noted,' issue from serpentinous rock from
which they evidently derive their magnesium contents. A few other
springs contain large amounts of magnesium that is apparently
derived from sources other than serpentine. Several of the desert
alkaline springs are of this character, but perhaps the most notable
are Alhambra Springs (Contra Costa 2, p. 293) and the group near
Santa Barbara, including Veronica Springs (Santa Barbara 3, p. 294).
These waters contain large amounts of magnesium, which is probably
derived from ocean water, although it has been concentrated by some
process that is not clearly understood.

MENDENHALL SPRINGS (ALAMEDA 5).
Mendenhall Springs are 11 miles byroad southeast of Livermore
on the steep southwestern side of the canyon of Arroyo Mocho,
500 feet above the stream. Two springs here seep from short pros-
pect tunnels 50 yards apart that were driven many years ago in search
of gold. The water was early noticed to be perceptibly mineralized,
the perceptible taste apparently being due to magnesia, and a number
of years ago it was bottled as Agua de Vida (Water of Life) Springs
Water.
The water of the southern spring is piped to a tank and furnishes
a domestic supply; the other spring supplies a watering trough in
the barnyard. Their flows are respectively about 1 gallon and
half a gallon a minute.