The Honolulu republican. [volume] (Honolulu, T.H.) 1900-1902, 1901-12-08
Value Of Volcanoes.

A volcano can be OF the greatest
/ service to biologists. Not only do
volcanoes serve as specimen coilec-
tors by bringing up fragments of rock
from otherwise inaccessible depths.
but they occasionally preserve yalu-
able evidence for geology by SPREAD
ing a mantle of lava over some soft
fossil-bearing rock that would other
wise soon disappear. In contribu-
tion TO La Nature paris NJ de Lap
parent describes in detail how some
particular volcanoes have thus done
service TO science. He says:
The deeper the excavation is the
more previous is the information
that it can furnish The geologist
always laments because be can not
descend deep enough for his invesu-
cations. and it is inexpressible JOY TO
him when the diamOnd-drill. in an ex-
ploratiCn made for some mining OPP
Grafton. brings up specimens from
depths Of five or six thousand feet.
Now this exploratory function. which
is always costly, is being exercised
OF has been exercised in the past by
certain volcanoes. TO the geOlOgist' 5
great profit Such are the ones where
the emission OF lava has been accom-
panied by explosions that are violent
enough TO hurl into the air not only
the bombs of scoria. but more or
less considerable part OF the mass on
which the volcano stands.
Especially valuable TO biologists
has been Vesuvius. or rather the semi
circular mountain that surrounds 1t.
This mountain, which is celebrated
in the history of geologic controyer-
sy is called Somma IL is formed by
layers of lava and debris of all kinds,
thrown up from depth which is now
invisible. being below the sea-evel
and covered with volcanic material
In this debris are found bits of gray
rock with marine shells, showing IN D.
the sub-Apennine stratum (of Monte
Mario near Romel forms the immed-
late subStratum OF the volcano.
Other fragments. formed with inn
pressions of plants. show that n con-
tinental period followed this marine
episode But the most instructive
bits are those which have long drawn
the attention OF mineralogists to Som
ma because of The rare and well chry
stabilized varieties that they include.
We now know past all doubt that
their origin must be sought in the
sedimentary limestones of different
epochs that form the backbone of the
Southern Apennines and exist in the
depths beneath the volcano. These
limestones. held under enormous
pressure in contact with the molten
matters and vapors at the base of
Vesuyius have undergone curious
transformations which may give us
the key 10 what biologists call met
amorphism, that is To say. the chang
es by which an old sediment may take
on a wholly crystalline form. Here.
then. the volcano has not only brought
up specimens for us from the bowels
OF the earth, but il has shown us the
results Of experiments that 1t has
made in its own wonderful labora-
tory"
Other geological volcanoes. the
writer tells Us, are those of the Isles
OF Sonda, which throw up mud often
mixed with interesting fossils from
inaccessible depths. the extinct vol
canoes of Auvergne. France. and even
that on the Isle of Arran, between
England mad Ireland. which has pre-
served under its ancient outpourings
of lava bits cf the earlier surface rock
OF the island. containing fossils that
would otherwise have been destroyed.