The age-herald. [volume] (Birmingham, Ala.) 1897-1902, 1902-05-19

| at the MOTIFS.
R. Howard of West Point, Miss, are at
the Morris.
Wade Allen OF Admission is at the Morris.
WEST INDIAN VOLCANOES.
From the New York Tribune.
The calamity which has just overtaken
two islands of the windward group In the
Antilles will unquest4onabIy lead to a
fresh discussion of the causes of volcanic
disturbance. All of the phenomena in
volved therein are not yet fully under
stood, and concerning some of them there
are perceptible differences of opinion
however, there is general agreement At
a depth of about thirty miles the internal
heat of the earth is probably great enough
to melt every known substance. Corffne-
m ent may keep In a rigid condition the
material which lies beneath the solid
crust but If an avenue of escape Is once
opened the stuff would soften and ooze
,
moreover, to recognize the Importance
of gravitation in producing eruptions.
The weight of several miles of rock is al
most inconceivabie, and It certainly ought
to compel potentially plastic" matter to
rise through any crevice that might be
newly formed. Russell, Gilbert and some
other authorities regard this as the chief
mechanical agent In an eruption. at least
when there is a considerable outpouring
of lava
AS to the extent to which water oper-
ates there Is like of harmony. among
volcanists. Shaler, Milne and others hold
that substance largely, If not entirely,
responsible for the trouble. They point
to the fact that many volcanoes are stu
ated near the coast of continents or on
islands, where leakage from the ocean
may possibly occur. Russell, on the other
factor, but as an occasional, though i'm
portant, reinforcement He suspects that
when the molten rock has risen to a
considerable distance 1t encounters that
fluid, perhaps in succession of pockets
and that steam is then suddenly sener-
ated The explosive effects which ensue
are of two kinds By the expansion of
the moisture which some of the lava
contains the latter is reduced to a state
of powder, and thus originate the enor-
nous clouds of fine dust which are eject
ed. Shocks of greater or less violence are
also produced. The less severe ones no
doubt sound like the discharge of artil-
lery and give rise to tremors In the I'M
mediate vicinity. In extreme cases enough
force is developed to rend the walls of
the volcano itself. Russell attributes the
blowing up of Krakatoa to steam. lie
eliminating episode of the Pelee eruption
last week. though not resulting so dis
astrously to the mountain. would seem
to be due to the same immediate cause.
To this particular explosion, too. 1t seems
safe to assign the upheaval which excited
tidal wave.
The precise manner In which the plas-
tic material inside of the terrestrial shell
gets access to the surface Is not entire
ly clear. Nevertheless, 1t is possible to
get some light on the matter It is we'll
known that in many places there are
deep cracks, or faults" in the earth 8
crust. Some of them in the remote past
have been wide and deep enough to ad-
NIT molten material from below. The
Palisades of the Hudson are believed to
have been formed by such an intrusion,
the adjacent rock on the eastern face
having since been worn away by the
weather or other agents. 1t has been OBJ
served that many volcanoes are distri-
buted along similar faults.
The existence of a chain of volcanic is
lands in the West Indies suggests the
probability that 1t follows a crack of great
antiquity, though the issue of lava and
ashes for several centuries may have
been limited to a few isolated points. Just
how these vents have been re-opened is
one of the most difficult questions still
weakness in the rocks. though, and a
susceptibility to fresh fracture is afford
ed. Professor MCGEE suggests that the
overlooking of the ocean bed by salt from
the Mississippi river or other source may
have been the Immediately exciting cause
of the recent outbreaks. Other biologists
have found a similar explanation accept
able in the case of eruptions elsewhere.
The theory has much to commend 1t to
favor.