Vermont phÅ“nix. [volume] (Brattleboro, Vt.) 1834-1955, 1858-04-24

gular mass, called the Moya, was uplifted from
the earth in numerous continuous conical ele-
vations, the whole being composed of carbon,
crystals of augite and the silicious shields of
infusoria. The eruption Of carbonic acid gas
from assures in the valley Of the Magdalene,
during the earthquake Of New Grenada, on the
10th of November 1927 suffocated many snakes,
rats, and other animals. Sudden changes of
weather. as the occurrence of the rainy season
in the tropics at an unusual period of the year,
have sometimes succeeded violent earthquakes
in Quito and Peru. DO gaseous fluids rise
from the interior of the earth and mix with the
atmosphere? or are these meteorological pro-
cesses the action Of atmospheric electricity dis
turbed by the earthquake? In the tropical
regions of America, where, sometimes, not
drop of rain falls for ten months together, the
natives consider the repeated shocks of earth
quakes-whch do not endanger the low reed
huts--as auspicious harbingcrs of frutfulness
and abundant rain.
The intimate connexion Of the phenomena
which we have considered is still in obscuritv.
Elastic fluids arc, doubtlessly, the cause of the
slight, and perfectly harmless, trembling of the
earths surface which has often continued for
several days (as in 1916, at Scaccia, in Sicily
before the volcanic elevation of the island of
Julia,) as well as % the terrific explosions, ac-
companied by loud noise. The focus of this
destructive agent, the seat of the moving force.
lies far below the earth's surface but We know
as little of the extent Of this depth as we know
of the chemical nature of these vapors that are
so highly compressed. At the edges of two
craters, Nesuvius and the towering rock which
projects beyond the great abyss of Pichincha,
near Quito, have felt periodic and very regu-
! lar shocks of earthquakes, on each occasion from
| twenty to thirty seconds before the burning
scoriae or gases were erupted. The intensity
of the shocks were increased in proportion to
the time intervening between them. and, conse-
quently to the length of time in which the va
pors were accumuating. This simple fact.
which has been attested by the evidence of so
many travellers, furnishes us with general So
luton of the phenomenon, in showing that ac-
, tive volcanoes are to be considered as safety
valves for the immediate neighborhood. The
danger of earthquakes increases when the open
ings of the volcano are closed and deprived OF
free communication with the atmosphere; but
the destruction of Lisbon, of Caracas, of Lima
of Cashmir, in ljj4, and of so many cities OF
Calabra, Syria, and Asia Minor, shows us, on
the whole, that the force of the shock is not the
greatest in the neighborhood of active volcanoes
The intelligent geographer of Amasea-to
whom we are indebted for the notice Of this cir
cumstance--further remarks =" Since the era
ters of Etna have been opened, which yield q
passage to the escape Of fire, and, since burning
masses and water have been elected. the country
near the sea-shore has not been so much shaker
as at the time previous to the separation
Sicily from Lower Italy, when all communica
tons with the external surface were closed"
We thus recognise in earthquakes the exis
tence of volcanic force which, although every
where manifested, and as generally difiused a
the internal heat of our planet, attans but rare
ly and then only at separate points, sutficien
intensity to exhibit the phenomenon of erup
tons. The formation of veins--that is to say
the filling up of assures with crystalline masses
bursting forth from the interior las basalt, mel
aphyre, and greensboro gradually disturbs thu
free intercommunication OF elastic yapors. Thi
tension acts in three different ways. either il
causing descriptions, or sudden and retroverseC
elevations, or, finally, as was first observed in
great part of Sweden, in producing changes il
the relative level of the sea and land, which al
though continuous, are only appreciable at in
tervals of long periods.