Gilpin observer., 1914-07-16
South American "Water Stone"
a Singular Phenomenon.
Scientists Disagree as to Process Of
Its Formation-PrincipaI Constitu-
ent ls SiIica-Is Found EN-
bedded In Black Lava.

There Is found in Uruguay and the
Argentine Republic a geological puz-
zie known to the English-speaking
people of those countries as the Salto
water stone"
IN appearance the average water
stone resembles a piece of clear glass
that has been fused by heat. The
stones vary in size from the bulk of
a iarKs egg to that of goose, but
larger specimens are sometimes found
lney are not uniform in shape. are
shsntly fiattened, and all are more
or less contorted. 1t is thought that
the principal constituent of the stone
ID silica. The rock in which it is
round embedded is a dense black lava.
Many stones contain no water and
tue more or less imperfect stones
seem 10 be numerous. These imper-
fect stones, however, serve, in meas
ure, to indicate how the water stone
is formed. For example, the appear
ance OF one stone clearly indicates
that the first formation of the stone
was abruptly stopped by some un-
known cause. When observed from
the concsve side it presents somewhat
the appearance of a copical seashell,
displaying irregular concentric circles.
IN the center of these circles there is
rounded indentation which indicates
with comparative certainty that the
inhltration Of water holding silica in
solution Is the cause of its formation.
AS already stated, the water stones
are found embedded in black lava
rock, which at one period was soft
ana plant from volcanic heat Silica
in molten state may have dripped
on 1t, possibly falling from great
height; and as this dripping continued
to bear on one point. the silica, which
slightly broadening out, would be de-
pressed In the center, thus causing the
underside to become convex or
pointed. and the continued augmenta-
tion OF material would cause the silica
gradually to sink in the lava.
Molten silica in cooling possesses
the property of remaining for some
time in soft. gelatinous condition.
but in heated atmosphere it would
remain plant infinitely longer. Thus
as the silica continued to sink the
lateral pressure of the lava on the
silica gradually brought its upper
edges together, and by the continued
dripping of the molten silica the close
ultimately became hermetic.
All this is theoretical, however,
since scientists are not agreed upon
the question. If the formation of the
water stones Is to be traced to the
more direct action OF molten silica,
the water they contain must have
found its way in by some means after
the stone was formed. II this be the
case. there seems to be only one ra-
'tional solution OF the problem-that
the stone after completion must have
been submerged In water for q long
time, possibly warm water. the heat
of which would have caused a slight
expansion In the silica. This being
united with pressure, in time the wa
ter may have filtered through to such
an extent as finally to fill the cavity.
Many hold that the water stone Is
a fraud. since, they assert. II it be
left exposed for any length Of time
evaporate and finally disappear. But
on the other hand, those who admit
that various cases of this have oc'
CURED point out that the evaporation
OF the water in all these instances was
probably due to slight fracture in
the stone, the result Of carelessness OF
want Of skill in the excavation.
It Is also pointed out that there are
many water stones that have lain In
museums and elsewhere from IL to II
years. and that during that compare
lively long period the water in tht
stones has shown no perceptible dimi
mutton. This. 1t is contended. Is SUN
cient proof that the water stone is no
fraud. but very singular phenom
enon.