W. L. (William Larkin) Webb.

Brief biography and popular account of the unparalleled discoveries of T.J.J. See .. online

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large enough to take off the island ridge and throw it in the trench,
it would about fill it up.

Now if we go along in a level plain and come to a mound, with
a depression by the side, of about the same volume, do we not
immediately conclude that the mound came out of the hole in
the ground, and that the mound-builders have been at work there?
And if we find not only one mound, but many, each accompanied
by an adjacent hole of corresponding volume, do we not infer that
the several mounds came out of the respective holes, and that the
whole group of mounds is the work of a colony of mound-builders?
Such a group of mounds once existed where the city of St. Louis
now stands, and for that reason the metropolis of the Mississippi
Valley often is called the Mound City.

Again, suppose the mounds were arranged in a line, with the
holes all on one side, and close together; a little shoveling would
convert them into a continuous trench with a bank on one side,
like an irrigation ditch. If we go into a level field and find such a
trench and adjacent embankment of equal volume, so that the
bank would fill up the depression, if shoveled in, we know that the
ditch diggers have been at work, and that the bank was made of
earth taken out of the ditch.

What we have here considered with regard to familiar sights
on the land, we encounter also in the bed of the sea. There are
islands with depressions or holes near them, of about equal volume;
and there are ridges or mountain ranges with trenches near them


of so nearly the same volume that the depressions could be filled
up by shoveling off the elevations. Thus we are led to conclude
that the elevations and the depressions are physically connected;
and that the elevations resulted from matter taken from under
the depressions, and transferred to its present position beneath the
adjacent range.

Now in the case of these inequalities on our level fields, some
process equivalent to surface shoveling was actually used. The
islands and mountain ranges in the sea, however, were formed by
a much mightier process; namely, by the expulsion of lava from
beneath the earth's crust, which pushes it up in one place, and
permits it to sink down in another, so that matter is transferred
from one place to the other by the movement of lava streams
beneath the cool, solid crust of the globe.

To understand how this takes place, let us consider the world-
shaking earthquakes which so frequently occur in the Aleutian
Islands. Major Button justly observes that this region is one
of the chief breeding-grounds of world-shakers. And if we com-
pare the distribution of earthquakes given in Milne's earthquake
map of the world, with this region, we shall find that the trench
and adjacent ridge run right through the center of the blackest
part of the great earthquake belt surrounding the Pacific Ocean.
This indicates that the earthquakes are concerned with the digging
out of the trench to the south of these islands, and with the eleva-
tion of the islands themselves, a number of which have been raised
above the water during the historical period. In fact three or
more new volcanoes in this range have broken out since these
islands were first explored by Europeans.

When a great earthquake occurs in the Aleutian Islands the
shaking frequently is so violent that persons cannot stand upon
their feet. In one well-known case further east, at Yakutat Bay,
Alaska, September 10-15, 1899, a party of explorers felt the shaking
so terribly that they could not stand on their feet and had to lie
on the ground; and while they were thus prostrate, expecting the
earth to open or an avalanche from the mountains to overwhelm


them, the adajcent sea was thrown into great eddies, and a huge
wave swept the shore, up-rooting the forests, and carrying the
helpless explorers some distance inland. By good fortune, how-
ever, they escaped without serious injury.

It may well be imagined that they were not altogether sur-
prised to find that great avalanches of stone and ice had slid down
the mountains, and vast glaciers had slipped into the sea, carrying
everything before them. Nay, worse still! The solid land of the
coast for over a hundred miles had been bodily uplifted many feet,
the maximum ascertained elevation being forty-seven feet and four
inches. Barnacles, and other marine animals were now sticking
to the rocks far above the reach of the highest tides, and furnished
conclusive proof of the mighty uplift of the earth's crust.

This great earthquake was carefully investigated in 1905 by
Professor R. S. Tarr, of Cornell University, and Lawrence Martin,
of the National Geographical Society. Their investigation as
published in the Bulletin of the Geological Society of America,
May, 1906, included photographs showing the barnacles still
sticking to the rocks. Now from what is shown here, it follows
that when the sea coast is upraised by an earthquake, as often
happens, lava is expelled from under the sea and pushed under the
land. It is in this way that mountains are formed along the coasts
and in the depths of the sea. The parallelism of the mountains to
the sea coast is familiar to every student of elementary geography.

It often happens in the Aleutian Islands that a great earth-
quake is followed by a so-called "tidal wave," or as it is more
properly called, a seismic sea wave. In the most important class
of these waves it is noticed that after the earthquake the water
withdraws from the shore, by a gradual draining away, as in the
tides, only more rapidly. Ships anchored in the harbor are often
left stranded, and the bottom laid bare, even when the previous
depth of the water was seven fathoms. But in an hour's time or
less, the sea returns as a great wave, which, near the shore, becomes
a mighty vertical wall of water, and carries everything before it.
Ships are thus washed a long distance inland, and many of them


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lost by dashing against rocks during the dreadful inundation of
the sea; and in the same way, cities lying near the sea level are
overflowed. In some cases they are first shaken down by the
earthquake, and then overwhelmed by the sea; so that Nature
seems bent on their utter destruction one calamity following
swift upon another.

Now the cause of the withdrawal of the sea from the shore is the
sinking of the sea bottom. The subsidence of the bed is indicated
by the way in which the water drains away. Lava has been ex-
pelled from beneath the sea bottom till the overlying crust becomes
unstable, and when it is again shaken in a great earthquake it
often gives down. The water then flows in on all sides to fill up
the depression in the sea level caused by the sudden drop of the
sunken area; and after a little while the currents meet in the center
of the depression, and by their mutual impact raise the depressed
level into a ridge. The flowing of the currents towards the center
of the depression draws the water away from the shore, so that
the ships are left stranded on the bare bottom and perfectly help-
less. And when the ridge upraised by the mutual impact of the
currents at length collapses by the gradual settlement of the water
under its own gravitation, a great wave is sent ashore to add to
the horrors of the earthquake.

Many cases of the sinking of the sea bottom are known, and
in some instances it is found that the drop amounted to hundreds
of fathoms. It is by this process of undermining and sinking that
the deep trench has been dug out near the Aleutian Islands. In
fact, Nature gives a clear indication of her own mighty processes;
for on the west coast of South America, in Japan, in the East Indies
and elsewhere, the coast often is upraised by the same earthquake
which causes the sinking of the sea bottom so clearly foretold by
the withdrawal of the sea and its return as a great wave.

The uplifting of the sea coast indicates that something has
been pushed under it, and the sinking of the adjacent sea bottom
shows that it has been undermined by the expulsion of the lava
which has been injected under the land. As the two areas are


side by side, and both movements occur in earthquakes which
disturb the intervening region most terribly (as if molten rock
were moving beneath the crust) it follows that a mass of lava is
expelled from under the sea and pushed under the neighboring
coast. This unquestionably is the general process in the greatest

The continuation of this process over long periods of time
gives rise to the expulsion of a vast quanity of lava from beneath
the sea, and the crust along the shore becomes upheaved into a
mighty ridge of mountains. In South America such uplifts of
the coast, with accompanying seismic sea waves, have often been
observed. This is the continuation of the process by which the
Andes were formed.

The coast of Chile was raised by the earthquake of 1822. And
in 1835, the movement was repeated on a still larger scale, in the
earthquake witnessed by Darwin and Fitzroy, who were then on
their famous voyage around the world. This disturbance raised
the coast five or six feet for several hundred miles, and the city of
Concepcion was totally destroyed.

On August 16, 1906, when Valparaiso was laid waste by one
of the most terrible earthquakes of modern times, it is said that
the coast was raised about ten feet. The earthquake of 1835 was
calculated by Lyell to have raised the coast by an amount cor-
responding to the bulk of Mt. Aetna; in other words, according
to our modern view, a bulk of lava equal to Mt. Aetna was pushed
under the shore, and the sea bottom correspondingly under-

Not only are the displacements of matter beneath the crust
large, but also in the same direction as those great movements of
the past, by which the mountains have been so greatly uplifted,
and the sea bottom so deeply sunk down.

For the beaches at Valparaiso were found by Darwin to have
been uplifted 1,300 feet in recent geological time; and more recent
travelers have found marine shells in the Andes at a height of at
least 15,000 feet. Thus we connect the fossils at the greatest


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Illustrating the New Theory that the Mountains are formed by the oceans, and thus run parallel
to the sea coast. From Frye's Complete Geography, by permission of Ginn & Co., Publishers.


altitude with the uplift of the sea coast by earthquakes, and may
affirm that most of our highest mountains were once beneath the
sea, and have since been raised to such great heights by the con-
tinuation of the earthquake process. The small uplifts of the
coast witnessed at the present time are but a part of the great
expulsions of lava from beneath the sea towards the land, which
resulted in development of mountains along the coasts and in the
depths of the ocean.

In this manner the Aleutian Islands are being raised into a
mighty mountain chain in the sea; eventually it will rise above
the water and connect North America with Asia, so that the Arctic
will be entirely cut off from the Pacific Ocean.

If now the question be asked why the earthquake and moun-
tain-forming forces are so powerful in certain places, and so feeble
in others, we reply that it is all due to the leakage under the hydro-
static pressure on the bottom resulting from the depth of the ocean.
The deeper the ocean becomes the greater the pressure on the
bottom, and the more water leaks through the crust, to form steam
beneath. The explosive vapor slowly accumulates, and when it
must have relief, the region shakes till a fault moves, and the crust
readjusts itself so as to give more space beneath. Fault is the
term used by geologists to denote a crack in the rocks of the earth's
crust, which is made up of blocks like pavement, only very much

It is observed that the earthquakes are always worst where
the sea is deepest, because the leakage there is greatest. If one
looks at a map of the ocean depths as laid down by the Coast-
Survey measurements, he may tell from the trenches in the sea
where the earthquakes are worst. These deep troughs always
follow the earthquake belts, or rather the earthquakes follow these
deep troughs, though some earthquakes occur remote from them.
The vast majority of the greatest earthquakes, however, always
occur near these dugout places in the sea bottom; as along the
coast west of South America, near Guam, in the Friendly Islands
of the Southern Pacific Ocean between Samoa and New Zealand,


in the East Indies, near the Phillipines, the Japanese, Kurile, and
Aleutian Islands.

It is well known that the worst earthquake country in the
world is Japan, and just east of these islands the sea over an area
of considerable extent is 4,600 fathoms deep. The hydrostatic
pressure at the bottom of the sea is here great enough to throw a
jet of water five and a half miles high. Is it any wonder that such
a pressure should force the water slowly into the bowels of the

The crust is made of solid rock, like granite, twenty miles
thick, yet under such a pressure as that exerted by the deepest
oceans, the water will slowly leak through, and form so much
steam in the underlying lava that it will swell and finally shake,
till it gets more space by pushing out at the edges.

The whole island of Nipon has thus been raised above the
ocean. If Nipon were dug off and thrown into the Tuscarora
Deep, it would just about fill up that immense depression. The
earthquakes in Japan are due to the fact that the islands are still
rising from the sea, and as the Tuscarora trench is deepening all
the time, Japan will always be greatly afflicted by earthquakes
and seismic sea waves.

The region of the Friendly Islands in the Southern Pacific
Ocean, between Samoa and New Zealand, affords a good illustra-
tion of the formation of mountains in the open sea at some distance
from a continent. Here two long, narrow connecting trenches are
dug out to a depth of over 4,000 fathoms; and on the west, just
parallel to the trenches, a mountain chain is lifting its crest above
the water, a few of the highest peaks already projecting as islands.

It is observed that the range always is formed on the side of
the trench opposite to the ocean, because the secular leakage of
the ocean causes the expulsion of the lava to be effected in the
direction of the land. The reason of this is that steam is formed
under the ocean, but scarcely at all under the land; and hence it
always works out towards the edges of the oceans, and thus walls
in the sea by high mountains about their borders.


Over half a century ago the veteran American geologist, J.
D. Dana, the famous professor at Yale College, noticed that the
highest mountains lie opposite the deepest oceans, and conversely-
He inferred that the relation of the extent and depth of the ocean
to the height and grandeur of the mountains about its borders was
of fundamental importance. Yet Dana did not perceive correctly
the real cause of mountain-making, for all geologists have hereto-
fore ascribed the formation of mountains to the shrinkage arising
from the secular cooling of the earth.

Even now many persons will be surprised to learn that this
old theory has no valid foundation in Nature, and will have to be
entirely abandoned. But such is the case. It will have to be
given up and thrown overboard, just like the more famous Ptole-
maic system of astronomy, which was finally overthrown by Coper-
nicus in 1543. Previous to that time Ptolemy's system had stood
the test of fourteen centuries, since the epoch of the school of
Alexandria, where the Almagest was composed in the reigns of
Hadrian and Antoninus Pius, about 140 A.D.

In the same way, the contraction theory is venerable from
age. It was vaguely hinted at by Newton, and in 1829 was given
its final form by the famous French geologist, Elie de Beaumont.
He held that the earth is cooling by the gradual dissipation of heat
into space, and the nucleus shrinking away from the crust; so that
at intervals the crust collapses to fill up the vacant space, and this
causes the rocks to be crumpled and pushed up into mountain
ranges formed along the lines of fracture.

If this theory were true the mountain chains ought to run in
any direction with respect to the oceans; and they certainly would
not always run parallel to the sea coast. In some cases at least
the mountains would run diagonally across the continents; yet
this never happens in practice, and we may be very sure that this
antiquated theory has no foundation whatever in actual Nature.

The doctrine of the secular cooling of the globe has behind it
the weight of ancient opinion, and still finds a place in most books
which deal with the earth's development. But as a matter of


fact secular cooling is of very little consequence, and the theory
is correspondingly misapplied in many of the sciences today.

In my investigations on the Temperature of the Earth recently
published by the American Philosophical Society at Philadelphia,
it is shown that the cooling is confined almost exclusively to the
crust of the globe, and that practically no shrinkage occurs from
the escape of heat from the deep interior, because the amount of
heat lost is altogether too small. Nor has such shrinkage been
appreciable at any time since the crust was formed, in the original
consolidation of the globe. Before the formation of a crust, when
the primordial consolidation had not yet begun, there may indeed
have been a considerable loss of heat from the incandescent sur-
face, but since the outer layers became cooled and encrusted,
and the oceans were formed from vapor previously floating in
the atmosphere, the effects of cooling have been very slight

We may easily convince ourselves of the correctness of this
view by recalling that no important changes now going on upon
the earth can be clearly ascribed to the effects of secular cooling.
The most important changes are those due to earthquakes, and
earthquakes certainly are not due to that cause; for if they were,
they would break out in the interior of the continents as well as
along the coasts and in the depths of the sea.

Is not an inland region such as Kansas or Sahara cooling as
much as an equal area of any sea coast? If cooling were the cause
of the great earthquakes, why should they occur near the sea and
not in high dry regions in the interior of the continents?

Moreover the Andes and the coast mountains in Alaska are
constantly shaken, while those in Colorado, far from the sea, are
never seriously disturbed. This shows that mountain-making
depends in some way upon the sea; and we have seen that it arises
from the leakage of the oceans, which develops steam beneath the
crust. This swells and finally shakes and pushes out some of the
saturated lava at the edges, so that the crust is uplifted into moun-
tains along the borders of the continents and in the sea.


Fossils now found far inland show that at one time the sea
covered the high plateaus of our western states, and extended to
the Rocky Mountains. The whole country west of Laramie,
Wyoming, has been raised out of the sea in recent geological times;
and earthquakes obviously have been the means of this great
uplift, which has widened the continent by a thousand miles, and
raised the plateaus about a mile above the sea.

In the same way the great plateaus in South America and in
Asia have been uplifted by earthquakes. The plateau of Tibet
is three miles above the sea, and bones of elephants and rhi-
noceroses now found there show that the uplift has occurred
within recent geological time, because those animals could not
live at that altitude. Accordingly they must have flourished
there when Tibet was only about a mile above the sea, and
the uplifting has since carried their bones to much greater

Perhaps the reader will agree that the process here outlined
for certain mountain chains is the true one, but yet ask whether
it is not possible that some have been formed by other causes, such
as the shrinkage of the globe? He may notice that all mountains
are not parallel to the sea coast, and thus imagine that such ex-
ceptional inland ranges were formed by a different cause. To
this conjecture we may reply that Nature has one uniform process,
and the formation in all cases is due to the same physical agency.
And while we have not yet explored the earth's surface sufficiently
to ascertain exactly how all the mountains were produced, we
may be sure that the cause is always the same.

That some mountains could be formed by one process and
some by another is inconceivable. We do not know the extent
of the sea in past geological ages, and until this unwritten history
is fully developed it may take centuries to do it properly -
we cannot make out the precise details by which all the moun-
tains were formed. But we have proved how they are formed in
the clearest cases, and as nearly all are parallel to the shore, as if
due to the expulsion of lava from beneath the sea, there can be no


possible doubt that we have found the true and universal cause of
mountain formation in general.

The chief purpose of earthquakes is to raise land above the sea.
These disturbances seem very destructive to animal and vegetable
life, and especially to mankind; but without them the earth would
still be entirely covered by the oceans, and none of the higher
forms of life could have been developed on our planet.

Though the cosmical purpose of earthquakes was not under-
stood by the ancients, the uplift of strata by these disturbances
was distinctly taught by Strabo; and he cited the presence of
shells far inland as proof of the former extent of the sea. These
views have long been held by investigators, but in recent years
Lord Kelvin and Sir G. H. Darwin have proved from their mathe-
matical researches on the tides and other phenomena that the
earth behaves as a solid, and hence does not have a liquid
nucleus, as geologists had long been led to suppose. On this
restricted view of the case, the uplift of the land above the sea
could not be explained.

The geologists therefore gave up the theory that the interior
of the earth is liquid, and the solid crust subject to uplifts, and
adopted the view that the globe is solid throughout. This con-
clusion, however, is unjustifiable; for just beneath the crust is a
layer which in earthquakes is shown to behave as a fluid. Molten
rock actually moves beneath the solid crust in great earthquakes,
and it is this enforced movement of the lava, some twenty miles
beneath our feet, under accumulating steam pressure, that shakes
down cities and often devastates whole countries.

When we have the oceans for an overlying tank of water, and
the incandescent nucleus of our globe for a furnace, the natural
arrangement is such that the leakage of the thin crust between the
water and the underlying fire, is likely to give rise to some gigantic
experiments. It is this secular leakage and nothing else which
produces earthquakes, volcanoes, mountain formation, the uplift
of islands and plateaus, seismic sea waves, and the feeble attraction
of mountains long since noticed in geodesy. Six great classes of

One of the most celebrated of the Andean Peaks. Encyclopedia Americana. From the Article, Andes, by special permission

A typical volcano, rising to an altitude of about 17,000 feet. Publications of the Sierra Club, June, 1911.


Photograph and copyright by Miss Anna S. Peck, National Geographical Magazine, for June, 1909.

Used by special permission of Miss Peck.

The highest Volcano in the world, and long considered the summit of the Andes.

Altitude, 22,800 feet.


phenomena are thus connected and shown to depend on a single
physical cause.

Volcanoes are only particular mountains, and it was noticed

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Online LibraryW. L. (William Larkin) WebbBrief biography and popular account of the unparalleled discoveries of T.J.J. See .. → online text (page 12 of 28)