Dr.. Smiths Lectures on Geology.
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nounced that in the Cornwall mines the copper
veins we're found to be hotter than the tin and
slate hatter than granite thus showing that the
best conductors are the hottest-which Is the best
explained upon the supPosition of the Earth's in
ternal heat. He spoke next of rocking-stone
found in England on which the supers,itious be-
lieved the Druids used to offer their sacrifices 1t
was merely boulder, he said, which had hap
pened to lodge upon point.


In regard to the theory OF boulders, he said he
should have less difficulty in understanding it if
we did not see that the boulders were not always
brought from great distances they sht have
been by ice-bergs when the whole country was un-
der water. But, he said, we often find them where
they could have been brought from only short
distance-as upon this sland and it is difficult to
see how they could have crossed rivers as they
must have done. In truth, Dr. S. said he did not
believe the true theory of boulders had yet been
reached.


Some years ago creek in Kentucky overAowed
its banks and washed away portion of the diluvi-
um. Some six or eight feet below the surface was
found stratum of Indian corn carbonized or con-
verted to charcoal, the cob being reduced to pow
der. This strata was six inches thick, and ex-
tended over so large region as would even at
present rates, require several years to raise suf
ficient amount. The fact is believed By those best
capable of judging; its solution Dr. S. could not
furnish. The Indians being known to be savages
it was not easy to see how this corn could have
been raised.


In order to explain Earthquakes DR.. S. said he
must revert to the primary condition of the Earth.
AS it cooled gradually it would naturally crack
and weak parts in its crust would be formed and
MS the internal forces pressed upward it would be
very natural that volcanoes should he formed.


This portion of North America is probably the
most quiet portion Of the globe-the most free
from volcanic disturbance. The Continent has
been upheaved with such equabity of power that
there are few faults other signs of disturbance.


While the granite was cooling and the water
condensng, the earth would be hotter than the air,
and evaporation would be going on. 1t is known
that evaporation increases the energy of electric
action; so that storms of thunder and lightning
must then have been much more violent than now.
And yet shocks of lightning in recent times have
been known to hurl immense rocks to great dis
tance; but In these ancient times we must suppose
them TO have been of even more enormous power.


In order to account for Earthquakes Dr. S.
thought 1t necessary to suppose the Earth filled with
liquid matter, with only cooled and solid crust
He could not otherwise explain the disturbance
of the whole Continent which was observed at a
great Earthquake in Lisbon. The only agent we
know of is steam; but Dr.. S. could not easily be-
lieve that the maximum force of steam could be
powerful enough to produce such results; for the
whole of North Africa and of Europe were up
heaved with an undulating motion at that time.


Coming now to volcanoes, DR.. Smith said he
he'd already explained some Of the phenoEsna
connected with them. They were produced in
consequence of some change in the interior of the
Earth, of what nature was not known. Sir
HUMPHREY DAvY supposed it must. be in conse-
quence of some of the metalloids coming in con-
tact with oxygen; but DR.. S. could not accept
this as true explanation; nor could he see how
volcanoes should remain quiet for such length
of time as vesuvius at different periods has done
We are told that in its crater the army of Sparta
Gus once encamped-not knowing what it was.
The early volcanoes seem to have preceded the ex-
islence of water, for the first matter thrown out
was solid plutonic pebbles, whereas the modern
lava is porous-evidently rendered so by water.


A single volcano is always necessarily concaI:
and unless the sides of equal strength the
lava would burst through; and this, toe, explains
the fact that nearly ali eruPtions are lateral The
quantity of matter elected by volcanoes is one of
the puzzles connected with them. The whole
body of Etna has been thrown up from the nte
rior of the Earth: so that either there must be
immense cavity in the Earth, or the Earth must
have collapsed. In Java there sunk at once
portion of land fifteen miles long and six wide ::


this tends to show that there must be cavity
within.


DR.. s. read from Mr.. LYELL an account of an
eruption in 1889 in the Sandwich Islands, which
filed up the channel of large river and threw
out an enormous amount of matter.


The character of lava differs at different times.
Sometimes it is very light-often light enough to
float. The older lava is generally very firm and
solid \ curious phenomenon is seen in the
Sandwich Islands. The lava thrown over the
mountain falls into shreds and becomes glass
called by the natives Pelees hair-beng supposed
TO be the hair of their favorite goddess.


The manner in which lava flows is very re-
narkable. 1t was found at Catana that it flowed
across valley and when it came to the wall of
the city it run to its top and passed over. 1t
seems at first difficult to see how a fluid can thus
ascend hill; but the explanation is found in the
fact that the sides becoming cool tube is formed
which thus conducts it up hill-1ising to its
orisisal level.


DR.. S. next spoke Of the upheaval and depres-
sion Of the various parts Of the globe. II is found
that the country around the Baltic Sea now rises
between five and six inches in a century. This
upheaval also is gradual. In South America an
immense tract was once raised some twelve feet at
ence. The remains Of the Temple of Scraps ex-
hibit this phenomenon in remarkable manner.
Upon the pillars yet standing are marks of the
lithodomi, small muscles which make their way
into marble and cannot get out again. 1t is sup
posed that the muscle elects certain acid which
eats into the marble, the life Of the animal pre-