earthquakes, whose oscillations on either side of the central region
of comparative rest may be compared to the swaying of a mighty see-saw
on either side of its point of support, should be capable of giving
birth to throes propelling sea-waves across the Pacific Ocean. The
throe actually experienced at any given place is relatively but an
insignificant phenomenon: it is the disturbance of the entire region
over which the throe is felt which must be considered in attempting
to estimate the energy of the disturbing cause. The region shaken by
the earthquake of 1868, for instance, was equal to at least a fourth
of Europe, and probably to fully one-half. From Quito southwards as
far as Iquique—or along a full third part of the length of the South
American Andes—the shock produced destructive effects. It was also
distinctly felt far to the north of Quito, far to the south of Iquique,
and inland to enormous distances. The disturbing forces which thus
shook 1,000,000 square miles of the earth’s surface must have been of
almost inconceivable energy. If directed entirely to the upheaval of a
land region no larger than England, those forces would have sufficed
to have destroyed utterly every city, town, and village within such a
region; if directed entirely to the upheaval of an oceanic region, they
would have been capable of raising a wave which would have been felt
on every shore-line of the whole earth. Divided even between the ocean
on the one side and a land region larger than Russia in Europe on the
other, those Vulcanian forces shook the whole of the land region, and
sent athwart the largest of our earth’s oceans a wave which ran in upon
shores 10,000 miles from the centre of disturbance with a crest thirty
feet high. Forces such as these may fairly be regarded as cosmical;
they show unmistakably that the earth has by no means settled down into
that condition of repose in which some geologists still believe. We
may ask with the late Sir Charles Lyell whether, after contemplating
the tremendous energy thus displayed by the earth, any geologist will
continue to assert that the changes of relative level of land and sea,
so common in former ages of the world, have now ceased? and agree
with him that if, in the face of such evidence, a geologist persists
in maintaining this favourite dogma, it would be vain to hope, by
accumulating proofs of similar convulsions during a series of ages, to
shake the tenacity of his conviction—
“Si fractus illabatur orbis,
Impavidum ferient ruinæ.”
But there is one aspect in which such mighty sea-waves as, in 1868 and
again in May, 1876, have swept over the surface of our terrestrial
oceans, remains yet to be considered.
The oceans and continents of our earth must be clearly discernible from
her nearer neighbours among the planets—from Venus and Mercury on the
inner side of her path around the sun, and from Mars (though under
less favourable conditions) from the outer side. When we consider,
indeed, that the lands and seas of Mars can be clearly discerned with
telescopic aid from our earth at a distance of forty millions of miles,
we perceive that our earth, seen from Venus at little more than half
this distance, must present a very interesting appearance. Enlarged,
owing to greater proximity, nearly fourfold, having a diameter nearly
twice as great as that of Mars, so that at the same distance her disc
would seem more than three times as large, more brightly illuminated
by the sun in the proportion of about five to two, she would shine
with a lustre exceeding that of Mars, when in full brightness in the
midnight sky, about thirty times; and all her features would of course
be seen with correspondingly increased distinctness. Moreover, the
oceans of our earth are so much larger in relative extent than those
of Mars, covering nearly three-fourths instead of barely one-half of
the surface of the world they belong to, that they would appeal as far
more marked and characteristic features than the seas and lakes of
Mars. When the Pacific Ocean, indeed, occupies centrally the disc of
the earth which at the moment is turned towards any planet, nearly the
whole of that disc must appear to be covered by the ocean. Under such
circumstances the passage of a wide-spreading series of waves over the
Pacific, at the rate of about 500 miles an hour, is a phenomenon which
could scarcely fail to be discernible from Venus or Mercury, if either
planet chanced to be favourably placed for the observation of the
earth—always supposing there were observers in Mercury or Venus, and
that these observers were provided with powerful telescopes.
It must be remembered that the waves which spread over the Pacific
on August 13–14, 1868, and again on May 9–10, 1876, were not only of
enormous range in length (measured along crest or trough), but also
of enormous breadth (measured from crest to crest, or from trough
to trough). Were it otherwise, indeed, the progress of a wave forty
or fifty feet high (at starting, and thirty-five feet high after
travelling 6000 miles), at the rate of 500 miles per hour, must
have proved destructive to ships in the open ocean as well as along
the shore-line. Suppose, for instance, the breadth of the wave from
crest to crest one mile, then, in passing under a ship at the rate
of 500 miles per hour, the wave would raise the ship from trough to
crest—that is, through a height of forty feet—in one-thousandth
part of an hour (for the distance from trough to crest is but half
the breadth of the wave), or in less than four seconds, lowering it
again in the same short interval of time, lifting and lowering it
at the same rate several successive times. The velocity with which
the ship would travel upwards and downwards would be greatest when
she was midway in her ascent and descent, and would then be equal to
about the velocity with which a body strikes the ground after falling
from a height of four yards. It is hardly necessary to say that small
vessels subjected to such tossing as this would inevitably be swamped.
On even the largest ships the effect of such motion would be most
unpleasantly obvious. Now, as a matter of fact, the passage of the
great sea-wave in 1868 was not noticed at all on board ships in open
sea. Even within sight of the shore of Peru, where the oscillation of
the sea was most marked, the motion was such that its effects were
referred to the shore. We are told that observers on the deck of a
United States’ war steamer distinctly saw the “peaks of the mountains
in the chain of the Cordilleras wave to and fro like reeds in a storm;”
the fact really being that the deck on which they stood was swayed to
and fro. This, too, was in a part of the sea where the great wave had
not attained its open sea form, but was a rolling wave, because of the
shallowness of the water. In the open sea, we read that the passage
of the great sea-wave was no more noticed than is the passage of the
tidal-wave itself. “Among the hundreds of ships which were sailing upon
the Pacific when its length and breadth were traversed by the great
sea-wave, there was not one in which any unusual motion was perceived.”
The inference is clear, that the slope of the advancing and following
faces of the great wave was very much less than in the case above
imagined; in other words, that the breadth of the wave greatly exceeded
one mile—amounting, in fact, to many miles.
Where the interval between the passage of successive wave-crests was
noted, we can tell the actual breadth of the wave. Thus, at the Samoan
Isles, in 1868, the crests succeeded each other at intervals of sixteen
minutes, corresponding to eight minutes between crest and trough.
But we have seen, that if the waves were one mile in breadth, the
corresponding interval would be only four seconds, or only one 120th
part of eight minutes: it follows, then, that the breadth of the great
wave, where it reached the Samoan Isles in 1868, was about 120 miles.
Now a wave extending right athwart the Pacific Ocean, and having a
cross breadth of more than 120 miles, would be discernible as a marked
feature of the disc of our earth, seen under the conditions described
above, either from Mercury or Venus. It is true that the slope of
the wave’s advancing and following surfaces would be but slight, yet
the difference of the illumination under the sun’s rays would be
recognizable. Then, also, it is to be remembered that there was not
merely a single wave, but a succession of many waves. These travelled
also with enormous velocity; and though at the distance of even the
nearest planet, the apparent motion of the great wave, swift though
it was in reality, would be so far reduced that it would have to be
estimated rather than actually seen, yet there would be no difficulty
in thus perceiving it with the mind’s eye. The rate of motion indeed
would almost be exactly the same as that of the equatorial part of the
surface of Mars, in consequence of the planet’s rotation; and this
(as is well known to telescopists), though not discernible directly,
produces, even in a few minutes, changes which a good eye can clearly
recognize. We can scarcely doubt then that if our earth were so
situated at any time when one of the great waves generated by Peruvian
earthquakes in traversing the Pacific, that the hemisphere containing
this ocean were turned fully illuminated towards Venus (favourably
placed for observing her), the disturbance of the Pacific could be
observed and measured by telescopists on that planet.
Unfortunately there is little chance that terrestrial observers will
ever be able to watch the progress of great waves athwart the oceans of
Mars, and still less that any disturbance of the frame of Venus should
become discernible to us by its effects. We can scarce even be assured
that there are lands and seas on Venus, so far as direct observation is
concerned, so unfavourably is she always placed for observation; and
though we see Mars under much more favourable conditions, his seas are
too small and would seem to be too shallow (compared with our own) for
great waves to traverse them such as could be discerned from the earth.
Yet it is well to remember the possibility that changes may at times
take place in the nearer planets—the terrestrial planets, as they
are commonly called, Mars, Venus, and Mercury—such as telescopic
observation under favourable conditions might detect. Telescopists
have, indeed, described apparent changes, lasting only for a short
time, in the appearance of one of these planets, Mars, which may fairly
be attributed to disturbances affecting its surface in no greater
degree than the great Peruvian earthquakes have affected for a time the
surface of our earth. For instance, the American astronomer Mitchel
says that on the night of July 12, 1845, bright polar snows of Mars
exhibited an appearance never noticed at any preceding or succeeding
observation. In the very centre of the white surface appeared a
dark spot, which retained its position during several hours: on the
following evening not a trace of the spot could be seen. Again the same
observer says that on the evening of August 30, 1845, he observed for
the first time a small bright spot, nearly or quite round, projecting
out of the lower side of the polar spot. “In the early part of the
evening,” he says, “the small bright spot seemed to be partly buried
in the large one. After the lapse of an hour or more my attention was
again directed to the planet, when I was astonished to find a manifest
change in the position of the small bright spot. It had apparently
separated from the large spot, and the edges alone of the two were now
in contact, whereas when first seen they overlapped by an amount quite
equal to one-third of the diameter of the small one. This, however,
was merely an optical phenomenon, for on the next evening the spots
went through the same apparent changes as the planet went through the
corresponding part of its rotation. But it showed the spots to be real
ice masses. The strange part of the story is that in the course of a
few days the smaller spot, which must have been a mass of snow and ice
as large as Novaia Zemlia, gradually disappeared. Probably some great
shock had separated an enormous field of ice from the polar snows, and
it had eventually been broken up and its fragments carried away from
the Arctic regions by currents in the Martian oceans. It appears to
me that the study of our own earth, and of the changes and occasional
convulsions which affect its surface, gives to the observation of such
phenomena as I have just described a new interest. Or rather, perhaps,
it is not too much to say that the telescopic observations of the
planets derive their only real interest from such considerations.
I may note in conclusion, that while on the one hand we cannot doubt
that the earth is slowly parting with its internal heat, and thus
losing century by century a portion of its Vulcanian energy, such
phenomena as the Peruvian earthquakes show that the loss of energy is
taking place so slowly that the diminution during many ages is almost
imperceptible. As I have elsewhere remarked, “When we see that while
mountain ranges were being upheaved or valleys depressed to their
present position, race after race and type after type lived out on the
earth the long lives which belong to races and to types, we recognize
the great work which the earth’s subterranean forces are still engaged
upon. Even now continents are being slowly depressed or upheaved, even
now mountain ranges are being raised to a different level, table-lands
are being formed, great valleys are being gradually scooped out; old
shore-lines shift their place, old soundings vary; the sea advances in
one place and retires in another; on every side nature’s plastic hand
is still at work, modelling and remodelling the earth, and making it
constantly a fit abode for those who dwell upon it.”
_STRANGE SEA CREATURES._
“We ought to make up our minds to dismiss as idle prejudices,
or, at least, suspend as premature, any preconceived notion of
what _might_, or what _ought to_, _be_ the order of nature, and
content ourselves with observing, as a plain matter of fact, what
_is_.”—Sir J. HERSCHEL, “Prelim. Disc.” page 79.
The fancies of men have peopled three of the four so-called elements,
earth, air, water, and fire, with strange forms of life, and have even
found in the salamander an inhabitant for the fourth. On land the
centaur and the unicorn, in the air the dragon and the roc, in the
water tritons and mermaids, may be named as instances among many of the
fabulous creatures which have been not only imagined but believed in
by men of old times. Although it may be doubted whether men have ever
invented any absolutely imaginary forms of life, yet the possibility
of combining known forms into imaginary, and even impossible, forms,
must be admitted as an important element in any inquiry into the origin
of ideas respecting such creatures as I have named. One need only look
through an illuminated manuscript of the Middle Ages to recognize the
readiness with which imaginary creatures can be formed by combining,
or by exaggerating, the characteristics of known animals. Probably
the combined knowledge and genius of all the greatest zoologists of
our time would not suffice for the invention of an entirely new form
of animal which yet should be zoologically possible; but to combine
the qualities of several existent animals in a single one, or to
conceive an animal with some peculiarity abnormally developed, is
within the capacity of persons very little acquainted with zoology,
nay, is perhaps far easier to such persons than it would be to an
Owen, a Huxley, or a Darwin. In nearly every case, however, the purely
imaginary being is to be recognized by the utter impossibility of
its actual existence. If it be a winged man, arms and wings are both
provided, but the pectoral muscles are left unchanged. A winged horse,
in like manner, is provided with wings, without any means of working
them. A centaur, as in the noble sculptures of Phidias, has the upper
part of the trunk of a man superadded, not to the hind quarters of a
horse or other quadruped, but to the entire trunk of such an animal,
so that the abdomen of the human figure lies _between_ the upper half
of the human trunk and the corresponding part of the horse’s trunk,
an arrangement anatomically preposterous. Without saying that every
fabulous animal which was anatomically and zoologically possible, had a
real antitype, exaggerated though the fabulous form may have been, we
must yet admit that errors so gross marked the conception of all the
really imaginary animals of antiquity, that any fabulous animal found
to accord fairly well with zoological possibilities may be regarded,
with extreme probability, as simply the exaggerated presentation of
some really existent animal. The inventors of centaurs, winged and
man-faced bulls, many-headed dogs, harpies, and so forth, were utterly
unable to invent a possible new animal, save by the merest chance, the
probability of which was so small that it may fairly be disregarded.
This view of the so-called fabulous animals of antiquity has been
confirmed by the results of modern zoological research. The merman,
zoologically possible (not in all details, of course, but generally),
has found its antitype in the dugong and the manatee; the roc in the
condor, or perhaps in those extinct species whose bones attest their
monstrous proportions; the unicorn in the rhinoceros; even the dragon
in the pterodactyl of the green-sand; while the centaur, the minotaur,
the winged horse, and so forth, have become recognized as purely
imaginary creatures, which had their origin simply in the fanciful
combination of known forms, no existent creatures having even suggested
these monstrosities.
It is not to be wondered at that the sea should have been more prolific
in monstrosities and in forms whose real nature has been misunderstood.
Land animals cannot long escape close observation. Even the most
powerful and ferocious beasts must succumb in the long run to man, and
in former ages, when the struggle was still undecided between some race
of animals and savage man, individual specimens of the race must often
have been killed, and the true appearance of the animal determined.
Powerful winged animals might for a longer time remain comparatively
mysterious creatures even to those whom they attacked, or whose flocks
they ravaged. A mighty bird, or a pterodactylian creature (a late
survivor of a race then fast dying out), might swoop down on his prey
and disappear with it too swiftly to be made the subject of close
scrutiny, still less of exact scientific observation. Yet the general
characteristics even of such creatures would before long be known.
From time to time the strange winged monster would be seen hovering
over the places where his prey was to be found. Occasionally it would
be possible to pierce one of the race with an arrow or a javelin; and
thus, even in those remote periods when the savage progenitors of the
present races of man had to carry on a difficult contest with animals
now extinct or greatly reduced in power, it would become possible to
determine accurately the nature of the winged enemy. But with sea
creatures, monstrous, or otherwise, the case would be very different.
To this day we remain ignorant of much that is hidden beneath the
waves of the “hollow-sounding and mysterious main.” Of far the greater
number of sea creatures, it may truly be said that we never see any
specimens except by accident, and never obtain the body of any except
by very rare accident. Those creatures of the deep sea which we are
best acquainted with, are either those which are at once very numerous
and very useful as food or in some other way, or else those which are
very rapacious and thus expose themselves, by their attacks on men,
to counter-attack and capture or destruction. In remote times, when
men were less able to traverse the wide seas, when, on the one hand,
attacks from great sea creatures were more apt to be successful,
while, on the other, counter-attack was much more dangerous, still
less would be known about the monsters of the deep. Seen only for a
few moments as he seized his prey, and then sinking back into the
depths, a sea monster would probably remain a mystery even to those
who had witnessed his attack, while their imperfect account of what
they had seen would be modified at each repetition of the story, until
there would remain little by which the creature could be identified,
even if at some subsequent period its true nature were recognized. We
can readily understand, then, that among the fabulous creatures of
antiquity, even of those which represented actually existent races
incorrectly described, the most remarkable, and those zoologically
the least intelligible, would be the monsters of the deep sea. We can
also understand that even the accounts which originally corresponded
best with the truth would have undergone modifications much more
noteworthy than those affecting descriptions of land animals or winged
creatures—simply because there would be small chance of any errors
thus introduced being corrected by the study of freshly discovered
specimens.
We may, perhaps, explain in this way the strange account given by
Berosus of the creature which came up from the Red Sea, having the body
of a fish but the front and head of a man. We may well believe that
this animal was no other than a dugong, or halicore (a word signifying
sea-maiden), a creature inhabiting the Indian Ocean to this day, and
which might readily find its way into the Red Sea. But the account of
the creature has been strangely altered from the original narrative,
if at least the original narrative was correct. For, according to
Berosus, the animal had two human feet which projected from each side
of the tail; and, still stranger, it had a human voice and human
language. “This strange monster sojourned among the rude people during
the day, taking no food, but retiring to the sea again at night, and
continued for some time teaching them the arts of civilized life.” A
picture of this stranger is said to have been preserved at Babylon
for many centuries. With a probable substratum of truth, the story in
its latest form is as fabulous as Autolycus’s “ballad of a fish that
appeared upon the coast, on Wednesday the fourscore of April, forty
thousand fathoms above water, and sang a ballad against the hard hearts
of maids.”
It is singular, by the way, how commonly the power of speech, or at
least of producing sounds resembling speech or musical notes, was
attributed to the creature which imagination converted into a man-fish
or woman-fish. Dugongs and manatees make a kind of lowing noise, which
could scarcely be mistaken under ordinary conditions for the sound of
the human voice. Yet, not only is this peculiarity ascribed to the
mermaid and siren (the merman and triton having even the supposed power
of blowing on conch-shells), but in more recent accounts of encounters
with creatures presumably of the seal tribe and allied races, the same
feature is to be noticed. The following account, quoted by Mr. Gosse
from a narrative by Captain Weddell, the well-known geographer, is
interesting for this reason amongst others. It also illustrates well
the mixture of erroneous details (the offspring, doubtless, of an
excited imagination) with the correct description of a sea creature
actually seen:—“A boat’s crew were employed on Hall’s Island, when
one of the crew, left to take care of some produce, saw an animal
whose voice was musical. The sailor had lain down, and at ten o’clock
he heard a noise resembling human cries, and as daylight in these
latitudes never disappears at this season” (the Antarctic summer),
“he rose and looked around, but, on seeing no person, returned to
bed. Presently he heard the noise again; he rose a second time, but
still saw nothing. Conceiving, however, the possibility of a boat
being upset, and that some of the crew might be clinging to detached
rocks, he walked along the beach a few steps and heard the noise more
distinctly but in a musical strain. Upon searching around, he saw an
object lying on a rock a dozen yards from the shore, at which he was
somewhat frightened. The face and shoulders appeared of human form and
of a reddish colour; over the shoulders hung long green hair; the tail
resembled that of the seal, but the extremities of the arms he could
not see distinctly. The creature continued to make a musical noise
while he gazed about two minutes, and on perceiving him it disappeared
in an instant. Immediately, when the man saw his officer, he told this
wild tale, and to add weight to his testimony (being a Romanist) he
made a cross on the sand, which he kissed, as making oath to the truth
of his statement. When I saw him he told the story in so clear and
positive a manner, making oath to its truth, that I concluded he must
really have seen the animal he described, or that it must have been the
effects of a disturbed imagination.”