Pittsburg dispatch. [volume] (Pittsburg [Pa.]) 1880-1923, 1890-11-23
VOLCANIC ACTIVITY.
Significance of the Fact That Erup-
tions Occur Near Waten
CRACKS IN THE OCEANS FL00B.
Two Streams That Flow From the ssa
Directly Into the Earth.
AN EPIDEMIC OF ACTIVITY VOW on

Something like an epidemic of volcanic
activity is in progress just at present. We
recently heard of the sudden eruption Of
Mombacho. volcano supposed to be ex.
tinct; then came the news that Kilauea ID
showing signs OF exceptional activity, and
now Etna has given warnings of an erup-
tion. These three occurrences in different
parts of the world can hardly be more than
a coincidence. but they drew attention to the
subject, which is very little understood,
says the London Saturday ReUisW.
Mombacho is a mountain about the SANG
height as Vesuvius, situated near the town
OF Granada, in Nicaragua, one of the Cen.
trail American Republics. 1t lies on the
shore OF Lake Nicaragua, between that and
the Pacific Ocean. The region abounds in
active volcanoes, but Mombacho has never
been counted among them. There is, Of
course, nothing new in the eruption of an
apparently extinct volcano, but the phe-
nomenon is sufficiently rare to be Interest,"
ing. Kilauea, on the other hand, is always
more or less active. It is not q mountain,
but an immense crater in the side of Mauna
Loa, one of the great volcanoes of the Sand
wich Islands.
SIGHTS IN KILAUEA.
As one of the wonders of the world, it has
been described by many travellers. The
main crater is nine miles in circumference,
but only small portion is usually IN full
activity. Adventurous sightseers descend
into the hollow amid jets of sulphurous
steam, walking on thin crust of lava, often
hot enough to burn the soles of their boots,
until they come within sight of the burning
cauldron at the bottom. The heaying sur
face, covered with sulphurous scum, and
the huge waves OF glowing molten lava
which are now and again cast into the air
or up against the rocks, to fall heavily back
into the solid sea, form one of the strangest
and grandest sights in nature.
About go years ago the crater was in full
activity, and continued SO for long time,
until in the year 1910 the weight of the lava
broke subterfanean passage, q miles long,
through the side of the mountain, and it
flowed into the sea. The lava stream was
altogether 40 miles in length and half a
mile wide. 1t took two days to reach the
sea, and continued flowing for three weeks.
THE GREATEST ERUPTION.
This was only excelled by the great erup-
tion of Skaptar, in Iceland, in 1888. The
long, II to 10 miles wide, and from 100 to
600 eet deep. 1t flowed in full force for
21l months and with gradually slackeuing
velocity for six months longer. The volume
of lava thrown out has been reekoned equal
TO the entire mass of Mont Blanc.
Much attention has been paid BY men Of
science to the laws regulating volcanic erup-
tions, but the only conclusions they seem to
have been able TO formulate amount to this:
That prolonged inactivity goes with severe
eruptions, frequent or incessant activity
with slight ones. This is not saying very
much, but it is interesting when taken with
the most generally accepted theory of the
cause OF eruptions. They are believed to be
due to steam generated from water adj
mitted through cracks in the earth's crust.
The required heat is as friction caused by
the crushing and grinding which accompany
the shrinking of the eaith's crust upon its
center; while the cracks, through which
water is admitted, are supposed to be at the
bottom of the sea, and are explained by SUBJ
sidence OF the ocean floor under the i'm
meuse weight of superintendent water,
amounting sometimes to several tons on the
square inch.
ALL ARE NEAR WATER.
All these are, of course, pure coniectures;
but there are several facts which lend them
probability. Almost all volcanoes are near
the sea; most are islands, and the rest on
the coast. The only real exceptions are the
two Than Shan volcanoes in Central Asia,
some 1, 500 miles from the sea; but they are
near large lakes which may supply its place.
OF the rest, the most distant from the sea are
Fragua Q56 miles), and Sangay 112 miles).
The latter is a mountain II 600 feet high,
one of the Quito group, and, curiously
enough, the most active of known volca-
noes.
1t has been continuously in eruption since
1928, and more than 23O explosions have
been counted In an hour, forming an almost
continuous roar If we consider the volume
of matter poured forth by such a mountain,
there is no difficulty in imagining cavity
beneath it vast enough to Communicate with
a crack in the bed oil the sea 100 miles
or so away. Another fact corroborating the
theory is that, according to the Challenger
and other deep-sea soundings, the deepest
holes in the floor Of the ocean occur in vol
canic areas.
RUNNING INTO THE GROUND.
Water NAV, however, be admitted into
the interior of the earth without supposing
a crack at the bottom OF the sea. The
phenomenon is to be witnessed in Europe,
and it is somewhat strange that the students
not appear to have had their attention di-
rected to the fact. In the island of Cephal-
lonia, one of the Ionian group, two streams
run directly from the sea into the land, and
disappear in the bowels of the earth,
The place where this occurs is about q
mile from Argostoli, small town and port.
The two streams are at no great distance
from one another, but quite independent.
One has been opened up for some hundreds
OF yards. 1t flows straight in from the sea
for few yards, then turns at right angles
and runs for some distance parallel with
the shore and close to it. Then it turns
again toward the sea, and, running of
course deeper and deeper, doubles COM
pletely under itself, thus forming q loop.
and finally passes out of sight deep down in
a landward direction. In this course it
turns two mills, which will give some idea
Of the strength of the current; one was
erected in 1885 by an Englishman, the Sec
Ond in 1859. There is no tide in The sea
here, and the flow OF the saltwater brook 10
perfectly steady and continuous.
no oExPLANATIoN OFFERED.
The other stream has only been opened
up short distance, but is of about the sama
size, and disappears in the ground in q
similar way. Argostoli is out OF the regu-
lar travelling routes, and only visited by
local traders and yachts, which will account
Tor this curious phenomenon having at
raeted so little attention. 1t is obvious that
hey flow into some subterranean reservoir,
and the ultimate destiny of the water is
quite satisfactorily explained by the theory
1f volcanic eruptions. We may imagine
that the reservoir Is emptied by periodical