The Helena independent. [volume] (Helena, Mont.) 1875-1943, 1892-07-31

Of the mate ial within the crater, and the
passage leading down ward. If the crater
has II thin floor and the passage below ia
partially open, or filed with molten lava,
the volcanic Rases can Escape upward and
outward with comparative quiet. But if
the passage is badly INSTRUCTED violent sx-
blossoms may take place, preceded by rumb-
linas. and even by earthquakes, far reach-
ing in effect.
In Hawaii the lavas arc very LIQUID, and
often are discharged quietly, but in 1868
a great eruption was accompanied by earth
quakes.
Where the sides of the volcano give way
before the floor of the crater or before the
hardened materials of the passage yield to
the upward preSSut e, assures occur in tho
mountain, generally diverging from the
cone toward the base and showing the red
hot mass within, if, indeed, as ia most
likely, lava IL not discharged from these
vents. Finally the lava in the assures cools
and binds the mountain together more
firmly than before.
At times lava may appear at the mouth of
the volcano without OVERLOOKING; or it may
break out Ill spots causing minor cones.
The force of volcanic EXPLOSIONS cannot
be comprehended, nor can the depths from
which material is thrown be stated. We
only know hat thousands and Thousands
of tons af ashes and both liquid and solid
rock are thrown from points far from the
crater OF the s%olcano, and that this force
which is sufficient for such exer.lous Ia
mighty. 1t is reported TINT the volcano
Antuco. in Chill, has thrown stones thirty
six miles md that Cotolaxi threw a block
weighing 200 tons for a distance of nine
miles.
Ashes thrown from volcanoes travel many
miles away and ca ry darkness with them.
In the year 1889 a volcano in Nicaragua
called Cossgulua caused darknoss in all
directions for a distance of tkirty-hve
miles. and deposited ashes, it is said, to q
depth of ten feet over twenty miles away,
while some of the minute volcanic dust was
car led up to a high current of air and fell
four days later 100 miles away, at Kingston,
Jamaica.
The ashes and other fine materials thrown
from volcanoes hre said to DO caused by the
action OF steam, which penstrates and di-
vides into minute particles the white-hot
lava, and whom the explosion which throws
out the liquid steam-laden lava occurs tho
once solid matter il scattered in dust.
The immense volumes of mud, ashes and
rock which are thrown from volcanoes
change entirely the surface of the surround
ing country, building up the well known
volcanic cones, and sometimes changing
miles upon miles of fertile lands, vine and
wood-clad hills into dssolate wastes. Trees,
animals. men, women. children, houses,
whole cities, like Herculaneum and Pom
poii, may be buried beneath the debris of
one volcanic eruption, to be hidden for
centuries and to disclose in later years the
life of historic ages.
An interesting change takes place in lava
as it issues forth. First. it is white hot and
flows like honey or melted iron. Next it il
red aud from redness changes to black with
all the SUGGESTIONS of color which NAV be
observed in a coal flung on a winters night
from a large old fireplace. Constantly
changing as it moves, the surface of the
lava stream finally becomes like cinders in