THE
MANUSCRIPT CONTINUED.
CHAPTER XXXI
A LESSON ON VOLCANOES.- PRIMARY COLORS ARE CAPABLE OF
FARTHER SUBDIVISION.
" Get into the boat," said my eyeless pilot, " and we will
proceed to the farther edge of the lake, over the barrier of which at great
intervals of time, the surface water flows, and induces the convulsion known as
Mount Epomeo."
We accordingly embarked, and a gentle touch of the lever enabled us rapidly to
skirt the shore of the underground sea. The soft, bright, pleasant earth-light
continually enveloped us, and the absence of either excessive heat or cold,
rendered existence delightful. The weird forms taken by the objects that
successively presented themselves on the shore were a source of continual
delight to my mind. The motion of our boat was constantly at the will of my
guide. Now we would skim across a great bay, flashing from point to point; again
we wound slowly through tortuous channels and among partly submerged stones.
" What a blessing this mode of locomotion would be to humanity," I
murmured.
" Humanity will yet attain it," he replied. " Step by step men
have stumbled along towards the goal that the light of coming centuries is
destined to illuminate. They have studied, and are still engaged in studying,
the properties of grosser forces, such as heat and electricity, and they will be
led by the thread they are following, to this and other achievements yet
unthought of, but which lie back of those more conspicuous."
We finally reached a precipitous bluff, that sprung to my view as by magic, and
which, with a glass-like surface, stretched upward to a height beyond the scope
of my vision, rising
straight from the surface of the lake. It was composed of a material seemingly
black as jet, and yet when seen under varying spectacular conditions as we
skirted its base it reflected, or emitted, most gorgeously the brilliant lines
of the rainbow, and also other colors hitherto unknown to me.
" There is something unique in these shades; species of color appear that I
can not identify; I seem to perceive colors utterly unlike any that I know as
the result of deflected, or transmitted, sunlight rays, and they look unlike the
combinations of primary colors with which I am familiar."
" Your observations are true; some of these colors are unknown on
earth."
" But on the surface of the earth we have all possible combinations of the
seven prismatic rays," I answered. " How can there be others here
?"
" Because, first, your primary colors are capable of further
subdivision."
" Second, other rays, invisible to men under usual conditions, also emanate
from the sun, and under favorable circumstances may be brought to the sense of
sight."
" Do you assert that the prism is capable of only partly analyzing the
sunlight?"
" Yes; what reason have you to argue that, because a triangular bit of
glass resolves a white ray into seven fractions that are, as men say,
differently colored, you could not by proper methods subdivide each of these
so-called primary shades into others? What reason have you to doubt that rays
now invisible to man accompany those capable of impressing his senses, and might
by proper methods become perceptible as new colors?"
" None," I answered; "only that I have no proof that such rays
exist."
" But they do exist, and men will yet learn that the term ‘ primitive '
ray, as applied to each of the seven colors of the rainbow, is incorrect. Each
will yet be resolved, and as our faculties multiply and become more subtle,
other colors will be developed, possessed of a delicacy and richness
indescribable now, for as yet man can not comprehend the possibilities of
education beyond the limits of his present condition."
During this period of conversation we skirted the richly colored bluff with a
rapid motion, and at last shot beyond it, as with a flash, into seeming vacancy.
I was sitting with my gaze directed toward the bluff, and when it instantly
disappeared, I rubbed my eyes to convince myself of their truthfulness, and as I
did so our boat came gradually to a stand on the edge of what appeared to be an
unfathomable abyss. Beneath me on the side where had risen the bluff that
disappeared so abruptly, as far as the eye could reach, was an absolute void. To
our right, and before and behind us, stretched the surface of that great smooth
lake on whose bosom we rested. To our left, our boat brushing its rim, a narrow
ledge, a continuation of the black, glass-like material, reached only a foot
above the water, and beyond this narrow brink the mass descended perpendicularly
to seemingly infinite depths. Involuntarily I grasped the sides of the boat, and
recoiled from the frightful chasm, over which I had been so suddenly suspended,
and which exceeded anything of a similar description that I had ever seen. The
immeasurable depth of the abyss, in connection with the apparently frail barrier
that held the great lake in its bounds, caused me to shudder and shrink back,
and my brain reeled in dizzy fright. An inexplicable attraction, however,
notwithstanding my dread, held me spell-bound, and although I struggled to shut
out that view, the endeavor failed. I seemed to be drawn by an irresistible
power, and yet I shuddered at the awful majesty of that yawning gulf which
threatened to end the world on which I then existed. Fascinated, entranced, I
could not help gazing, I knew not how long, down, down into that fathomless,
silent profundity. Composing myself, I turned a questioning glance on my guide.
He informed me that this hard, glass-like dam, confined the waters of the slowly
rising lake that we were sailing over, and which finally would rise high enough
to overflow the barrier.
" The cycle of the periodic overflow is measured by great intervals,"
he said; " centuries are required to raise the level of the lake a fraction
of an inch, and thousands of years may elapse before its surface will again
reach the top of the adamantine wall. Then, governed by the law that attracts a
liquid to itself, and heaps the teaspoon with liquid, the water of the quiet
lake piles upon this narrow wall, forming a ledge along its summit. Finally the
superimposed surface water gives way, and a skim of water pours over into the
abyss."
He paused ; I leaned over
and meditated, for I had now accustomed myself to the situation.
" There is no bottom," I exclaimed.
" Upon the contrary," he answered, " the bottom is less than ten
miles beneath us, and is a great funnel-shaped orifice, the neck of the funnel
reaching first down and then upward from us diagonally toward the surface of the
earth. Although the light by which we are enveloped is bright, yet it is
deficient in penetrating power, and is not capable of giving the contour of
objects even five miles away, hence the chasm seems bottomless, and the gulf
measureless."
" Is it not natural to suppose that a mass of water like this great lake
would overflow the barrier immediately, as soon as the surface reached the upper
edge, for the pressure of the immense volume must be beyond calculation."
" No, for it is height, not expanse, which, as hydrostatic engineers
understand, governs the pressure of water. A liquid column, one foot in width,
would press against the retaining dam with the force of a body of the same
liquid, the same depth, one thousand miles in extent. Then the decrease of
gravity here
permits the molecular attraction of the water's molecules to exert itself more
forcibly than would be the case on the surface of the earth, and this holds the
liquid mass together more firmly."
" See," he observed, and dipping his finger into the water he held it
before him with a drop of water attached thereto ( Figure 27 ), the globule
being of considerable size, and lengthened as though it consisted of some
glutinous liquid.
" How can a thin stratum of water give rise to a volcanic eruption?" I
next queried. " There seems to be no melted rock, no evidence of intense
heat,either beneath or about us." FIG. 27.
" I informed you some time ago that I would partially explain these facts.
Know then, that the theories of man concerning volcanic eruptions, in connection
with a molten interior of the earth, are such as are evolved in ignorance of
even the subsurface of the globe. The earth's interior is to mankind a sealed
chamber, and the wise men who elucidate the curious theories concerning natural
phenomena occurring therein are forced to draw entirely upon their imagination.
Few persons realize the paucity of data at the command of workers in science.
Theories concerning the earth are formulated from so little real knowledge of
that body, that our science may be said to be all theory, with scarcely a trace
of actual evidence to support it. If a globe ten inches in diameter be covered
with a sheet of paper, such as I hold in my hand, the thickness of that sheet
will be greater in proportion to that of such a globe than the depth men have
explored within the earth is compared with the thickness of the crust of the
earth. The outer surface of a pencil line represents the surface of the earth;
the inner surface of the line represents the depth of man's explorations; the
highest mountain would be represented by a comma resting on the line. The
geologist studies the substances that are thrust from the crater of an active
volcano, and from this makes conjectures regarding the strata beneath, and the
force that casts the excretions out. The results must with men, therefore,
furnish evidence from which to explain the cause. It is as though an anatomist
would form his idea of the anatomy of the liver by the secretion thrown out of
that organ, or of the lung texture by the breath and sputum. In fact, volcanoes
are of several descriptions, and usually are extremely superficial. This lake,
the surface of which is but one hundred and fifty miles underground, is the
mother of an exceptionally deep one. When the water pours over this ledge it
strikes an element below us, the metallic base of salt, which lies in great
masses in some portions of the earth's crust. *
Then an immediate chemical
reaction ensues, the water is dissociated, intense heat results, part of the
water combines with the metal, part is vaporized as steam, while part escapes as
an inflammable gas. The sudden liberation of these gases causes an irregular
pressure of vapor on the surface of the lake, the result being a throbbing and
rebounding of the attenuated atmosphere above, which, in gigantic waves, like
swelling tides, dashes great volumes of water over the ledge beside us, and into
the depth below. This water in turn reacts on fresh portions of the metallic
base, and the reflex action increases the vapor discharges, and as a consequence
the chamber we are in becomes a gasholder, containing vapors of unequal gas
pressures, and the resultant agitation of the lake from the turmoil continues,
and the pulsations are repeated until the surface of the lake is lowered to such
a degree as at last to prevent the water from overflowing the barrier. Finally
the lake quiets itself, the gases slowly disappear by earth absorption, and by
escape from the volcanic exit, and for an unrecorded period of time thereafter
the surface of the lake continues to rise slowly as it is doing now."
" But what has this phenomenon to do with the volcano?"
" It produces the eruption; the water that rushes down into the chasm,
partly as steam, partly as gas, is forced onward and upward through a crevice
that leads to the old crater of the presumed extinct but periodically active
Mount Epomeo. These gases are intensely heated, and they move with fearful
velocity. They tear off great masses of stone, which the resultant energy
disturbances, pressure, gas, and friction, redden with heat. The mixture of
gases from the decomposed water is in large amount, is burning and exploding,
and in this fiery furnace amid such convulsions as have been described, the
adjacent earth substance is fused, and even clay is melted, and carried on with
the fiery blast. Finally the current reaches the earth's surface through the
funnel passage, the apex of which is a volcano- the blast described a volcanic
eruption."
" One thing is still obscure in my mind," I said. " You assert
that the reaction which follows the contact of the flowing water and metallic
bases in the crevice below us liberates the explosive gases, and also volumes of
vapor of water. These gases rush, you say, and produce a volcanic eruption in a
distant part of the crust of the earth. I can not understand why they do not
rush backward as well, and produce another eruption in Kentucky. Surely the
pressure of a gas in confinement is the
same in all directions, is it not?"
" Yes," he replied, " but the conditions in the different
directions are dissimilar. In the direction of the Kentucky cavern, the passage
is tortuous, and often contracts to a narrow crevice. In one place near the
cavern’s mouth, as you will remember, we had to dive beneath the surface of a
stream of water. That stratum of water as effectually closed the exit from the
Earth as the stopper prevents water from escaping from a bottle. Between the
point we now occupy and that water stopper, rest thousands of miles of quiescent
air. The inertia of a thousand miles of air is beyond your comprehension. To
move that column of air by pushing against this end of it, and thus shoving it
instantly out the other end, would require greater force than would burst the
one hundred and fifty miles of inelastic stone above us. Then, friction of the
sides is another thing that prevents its accomplishment. While a gradually
applied pressure would in time overcome both the inertia of the air and the
friction of the stone passages, it would take a supply of energy greater than
you could imagine to start into motion the elastic mass that stands as solid and
immovable as a sentinel of adamant, between the cavern you entered, and the spot
we now occupy. Time and energy combined would be able to accomplish the result,
but not under present conditions.
In the other direction, a broad, open channel reaches directly to and connects
with the volcanic shaft. Through this channel the air is in motion, moving
towards the extinct crater, being supplied from another surface orifice. The
gases liberated in the manner in I have described, naturally follow the line of
least resistance. They turn at once away from the inert mass of air that rests
behind us, and move with increasing velocity towards the volcanic exit. Before
the pressure that might be exerted towards the Kentucky cavern would have more
than compressed the intervening column of air enough to raise the water of a
well from its usual level to the surface of the earth, the velocity in the other
direction would have augmented prodigiously, and with its increased rapidity a
suction would follow more than sufficient to consume the increasingly abundant
gases from behind.”
“ Volcanoes are therefore local, and the interior of the earth is not a molten
mass as I have been taught,” I exclaimed.
He answered: “ If men were far enough along in their thought journey ( for the
evolution of the mental side of man is a journey in the world of thought ), they
would avoid such
theories as that which ascribes a molten interior to the earth. Volcanoes are
superficial. They are as a rule, when in activity but little blisters or
excoriations upon the surface of the earth, although their underground
connections may be extensive. Some of them are in a continual fret with frequent
eruptions, others, like the one under consideration, awaken only after great
periods of time. The entire surface of this globe has been or will be subject to
volcanic action. The phenomenon is one of the steps in the world-making,
matter-leveling process. When the deposit of substances that I have indicated,
and of which much of the earth's interior is composed, the bases of salt,
potash, and lime and clay is exhausted, there will be no further volcanic action
from this cause, and in some places, this deposit has already disappeared, or is
covered deeply by layers of earth that serve as a protection."
" Is water, then, the universal cause of volcanoes?"
" Water and air together cause most of them. The action of water and its
vapor produces from metallic space dust, limestone, and clay soil, potash and
soda salts. This perfectly rational and natural action must continue as long as
there is water above, and free elementary bases in contact with the earth
bubbles. Volcanoes, earthquakes, geysers, mud springs, and hot springs, are the
natural result of that reaction. Mountains are thereby forming by upheavals from
beneath, and the corresponding surface valleys are consequently filling up,
either by the slow deposit of the matter from the saline water of hot springs,
or by the sudden eruption of a new or presumably extinct volcano."
" What would happen if a crevice in the bottom of the ocean should conduct
the waters of the ocean into a deposit of metallic bases?"
" That often occurs," was the reply; " a volcanic wave results,
and a volcano may thus rise from the ocean's depths."
" Is there any danger to the earth itself? May it not be riven into
fragments from such a convulsion?" I hesitatingly questioned.
" No; while the configuration of continents is continually being altered,
each disturbance must be practically superficial, and of limited area."
" But," I persisted, " the rigid, solid earth may be blown to
fragments; in such convulsions a result like that seems not impossible."
" You argue from an erroneous hypothesis. The earth is neither rigid nor
solid."
" True," I answered. " If it were solid I could not be a hundred
miles beneath its surface in conversation with another being; but there can not
be many such cavities as that which we are now traversing, and they can not
surely extend entirely through its mass; the great weight of the superincumbent
material would crush together the strongest materials, if a globe as large as
our earth were extensively honeycombed in this
manner."
" Quite the contrary," he replied; " and here let me, for the
first time, enlighten you as to the interior structure of the terrestrial globe.
The earth-forming principle consists of an invisible sphere of energy that,
spinning through space, supports the space dust which collects on it, as dust on
a bubble. By gradual accumulation of substance on that sphere a hollow ball has
resulted, on the outer surface of which you have hitherto dwelt. The crust of
the earth is comparatively thin, not more than eight hundred miles in average
thickness, and is held in position by the central sphere of energy that now
exists at a distance about seven hundred miles beneath the ocean level. The
force inherent to this sphere manifests itself upon the matter which it supports
on both sides, rendering matter the
lighter the nearer it lies to the center sphere. In other words, let me say to
you: " The crust, or shell, which I have just described as being but about
eight hundred miles in thickness,
is firm and solid on both its convex and concave surface, but gradually loses in
weight, whether we penetrate from the outer surface toward the center, or from
any point of the inner surface towards the outside, until at the central sphere
matter has no weight at all. Do you conceive my meaning?"
" Yes," I replied; " I understand you perfectly."
After a pause my pilot asked me abruptly:
" What do you most desire?"
The question caused my mind to revert instantly to my old home on the earth
above me, and although I felt the hope of returning to it spring up in my heart,
the force of habit caused me involuntarily to answer, " More light!"
" More light being your desire, you shall receive it."
Obedient to his touch, the bow of the boat turned from the gulf we had been
considering towards the center of the lake; the responsive craft leaped forward,
and in an instant the obsidian parapet disappeared behind us. On and over the
trackless waste of glass-like water we sped, until the dead silence became
painfully oppressive, and I asked:
" Whither are we bound?"
" Towards the east."
The well-timed answer raised my spirits; I thought again that in`this man,
despite his repulsive shape, I beheld a friend, a brother; suspicion vanished,
and my courage rose. He touched the lever, and the craft, subject to his will,
nearly rose from the water, and sped with amazing velocity, as was evident from
the appearance of the luminous road behind us. So rapid was our flight that the
wake of the boat seemed as if made of rigid parallel lines that disappeared in
the distance, too quick for the eye to catch the tremor.
Continuing his conversation, my companion informed me that he had now directed
the bark toward a point east of the spot where we struck the shore, after
crossing the lake, in order that we might continue our journey downward,
diagonally to the under surface of the earth crust.
" This recent digression from our journey proper," said he, " has
been made to acquaint you with a subject, regarding which you have exhibited a
curiosity, and about which you have heretofore been misinformed; now you
understand more clearly part of the philosophy of volcanoes and earthquakes. You
have yet much to learn in connection with allied phenomena, but this study of
the crude exhibition of force-disturbed matter, the manipulation of which is
familiar to man under the above names, is an introduction to the more wonderful
study destined yet to be a part of your field, an investigation of quiescent
matter, and pure motion."
" I can not comprehend you," I replied, " as I stated once before
when you referred to what you designated as pure motion."