Idaho semi-weekly world. [volume] (Idaho City, Idaho Territory) 1875-1908, 1891-11-17
UTILITY OF VOLCANOES.
The Pulverized Material which They
Throw Out of Value to the Soil.

1
Throw Out of Value to the Soil.
The solid matter thrown out by vol.
canoes is the most important contribu-
ton to the materials which the sea has at
its disposal for the nourishment OF its
life and for the formation of strata. The
quantity of the pumiceous and finely
pulverized material is enormous. When
it falls upon the sea it either floats for a
time or at once sinks into the depths. In
| either case it is, to great extent, dis
solved in the ocean waters, and 80 con-
tributes to the store of materials which
may be appropriated by the organic life
of the sea. When it falls on the land, it
is generally so incoherent that it is easily
| swept away by the rains, and SO comes
quickly into the ocean. The Importance
of this contribution to marine sediments
has been overlooked by biologists, but it
is easy to see that it may amount in mass
to something like as much as the earthly
matter which is brought to the sea by
| the rivers.
The volcanoes Of the Java district alone
within century throws out a mass of
this fragmentary rock amounting proba-
bly, to not less than 100 cubic miles, and
| perhaps to twice this quantity. Now, the
Mississippi river carries out in the form
of dissolved matter. mud and sand about
one cubic mile in twenty years, or five
cubic miles in century; thus these vol
canoes of the Java district have brought
up from the depth of the earth and con-
| tributed to the sea many times as much
detritus as has been conveyed to the
| ocean by the greatest river in North
America. Allowing for the greater poros-
| ity of the volcanic dust, it still seems not
unlikely that the elections from half
dozen great volcanoes of the East Indian
archipelago in period of a little more
than century, from 1872 to 1888, far
exceeded that brought into the ocean by
all the rivers of North America in the
same period.
Although the volcanoes of this district
| are by far the most powerful which are
known, we still cannot fairly reckon that
| their elections represent anywhere near
the half of the total quantity which came
| to the earth's surface from such vents
| during the above named period of III
years. For during this time some scores
of great craters were in eruption, includ-
| ing Skaptar, in Iceland, Vesuvius, Etna,
| various volcanoes in South America and
l
elsewhere. 1t seems, therefore, not I'M
likely that the solid material contributed
| by volcanoes to the sea floor may, on the
| average, amount to as much as that taken
| by the rivers from the land.
Among the solid substances which are
elected by volcanoes we find some of the
most indispensable elements Of organic
life, including phosphorus, soda, potash
and other materials. The value of these
materials to vegetation may be judged
| by the fertility which so often character
ICES the regions in the immediate vicinity
of volcanic cones which cast forth large
amounts of ash. If the rainfall be suffi-
cient this ash quickly decomposes into
fertile soil, which tempts the husband
man to replant the fields as fast as they
are ravaged by the explosion. Were it
| not for the constant return of these
rarer and precious materials to the su-
perficial part of the earth by means of
| volcanic action. it is likely that the
earth's surface would want many of the
| substances most necessary for organic
| life. We thus see that volcanoes play
very important part i'll the physical his
| tory of our planet. The action is, in a
largo degree, restorative. They help to
| maintain the earth's surface in condl-
| ton in which it may nurture hfe.-Cin-
cinnati Commercial Gazette.