THE PHOSPHORESCENCE OF THE SEA.
He who still lingers on the shore after the shades of evening have descended, not seldom enjoys a most magnificent spectacle; for lucid flashes burst from the bosom of the waters, as if the sea were anxious to restore to the darkened heavens the light it had received from them during the day. On approaching the margin of the rising flood to examine more closely the sparkling of the breaking wave, the spreading waters seem to cover the beach with a sheet of fire. Each footstep over the moist sands elicits luminous star-like points, and a splash in the water resembles the awakening of slumbering flames.
The same wonderful and beauteous aspect frequently gladdens the eye of the navigator who ploughs his way through the wide deserts of ocean, particularly if his course leads him through the tropical seas.
"When a vessel," says Humboldt, "driven along by a fresh wind, divides the foaming waters, one never wearies of the lovely spectacle their agitation affords; for, whenever a wave makes the ship incline sideways, bluish or reddish flames seem to shoot upwards from the keel. Beautiful beyond description is the sight of a troop of dolphins gambolling in the phosphorescent sea. Every furrow they draw through the waters is marked by streaks of intense light. In the Gulf of Cariaco, between Cumana and the peninsula of Maniquarez, this scene has often delighted me for hours."
But even in the colder oceanic regions the brilliant phenomenon appears from time to time in its full glory. During a dark and stormy September night, on the way from the Sea-lion island, Saint George, to Unalaschka, Chamisso admired as beautiful a phosphorescence of the ocean as he had ever witnessed in the tropical seas. Sparks of light, remaining attached to the sails that had been wetted by the spray, continued to glow in another element. Near the south point of Kamtschatka, at a water-temperature hardly above freezing point, Ermann saw the sea no less luminous than during a seven months' sojourn in the tropical ocean. This distinguished traveller positively denies that warmth decidedly favours the luminosity of the sea.
At Cape Colborn, one of the desolate promontories of the desolate Victoria Land, the phosphoric gleaming of the waves on the 6th September, when darkness closed in, was so intense that Simpson assures us he had seldom seen anything more brilliant. The boats seemed to cleave a flood of molten silver, and the spray dashed from their bows, before the fresh breeze, fell back in glittering showers into the deep.
Mr. Charles Darwin paints in vivid colours the magnificent spectacle presented by the sea, while sailing in the latitudes of Cape Horn on a very dark night.
There was a fresh breeze, and every part of the surface, which during the day is seen as foam, now glowed with a pale light. The vessel drove before her bows two billows of liquid phosphorus, and in her wake she was followed by a milky train. As far as the eye reached, the crest of every wave was bright, and the sky above the horizon, from the reflected glare of these livid flames, was not so utterly obscure as over the rest of the heavens.
While "La Venus" was at anchor before Simon's Town, the breaking of the waves produced so strong a light that the room in which the naturalists of the expedition were seated was illumined as by sudden flashes of lightning. Although more than fifty paces from the beach where the phenomenon took place, they tried to read by this wondrous oceanic light, but the successive glimpses were of too short duration to gratify their wishes.
Thus we see the same nocturnal splendour which shines forth in the tropical seas, and gleams along our shores, burst forth from the arctic waters, and from the waves that bathe the southern promontories of the old and the new worlds.
But what is the cause of the beautiful phenomenon so widely spread over the face of ocean? How comes it that at certain times flames issue from the bosom of an element generally so hostile to their appearance?
Without troubling the reader with the groundless surmises of ancient naturalists, or repeating the useless tales of the past, I shall at once place myself with him on the stage of our actual knowledge of this interesting and mysterious subject. It is now no longer a matter of doubt that many of the inferior marine animals possess the faculty of secreting a luminous matter, and thus adding their mite to the grand phenomenon. When we consider their countless multitudes, we shall no longer wonder at such magnificent effects being produced by creatures individually so insignificant.
In our seas it is chiefly a minute gelatinous animal, the Noctiluca miliaris, most probably an aberrant member of the infusorial group, which, as it were, repeats the splendid spectacle of the starry heavens on the surface of the ocean. In form it is nearly globular, presenting on one side a groove, from the anterior extremity of which issues a peculiar curved stalk or appendage, marked by transverse lines, which might seem to be made use of as an organ of locomotion. Near the base of this tentacle is placed the mouth, which passes into a dilatable digestive cavity, leading, according to Mr. Huxley, to a distinct anal orifice. From the rather firm external coat proceed thread-like prolongations through the softer mass of the body, so as to divide it into irregular chambers. This little creature, which is just large enough to be discerned by the naked eye when the water in which it may be swimming is contained in a glass jar exposed to the light, seems to feed on diatoms, as their loricæ may frequently be detected in its interior. It multiplies by spontaneous fission, and the rapidity of this process may be inferred from the immensity of its numbers. A single bucket of luminous sea-water will often contain thousands, while for miles and miles every wave breaking on the shore expands in a sheet of living flame. It was first described by Forster in the Pacific Ocean; it occurs on all the shores of the Atlantic, and the Polar Seas are illuminated by its fairy light. "The nature of its luminosity," says Dr. Carpenter, "is found by microscopic examination to be very peculiar; for what appears to the eye to be a uniform glow is resolvable under a sufficient magnifying power into a multitude of evanescent scintillations, and these are given forth with increased intensity whenever the body of the animal receives any mechanical shock."
The power of emitting a phosphorescent light is widely diffused both among the free-swimming and the sessile Cœlenterata. Many of the Physophoridæ are remarkable for its manifestation, and a great number of the jelly-fishes are luminous. Our own Thaumantias lucifera, a small and by no means rare medusid, displays the phenomenon in a very beautiful manner, for, when irritated by contact of fresh water, it marks its position by a vivid circlet of tiny stars, each shining from the base of a tentacle. A remarkable greenish light, like that of burning silver, may also be seen to glow from many of our Sertularians, becoming much brighter under various modes of excitation.
Among the Ctenophora the large Cestum Veneris of the Mediterranean is specially distinguished for its luminosity, and while moving beneath the surface of the water gleams at night like a brilliant band of flame.
The Sea-pens are eminently phosphorescent, shining at night with a golden-green light of a most wonderful softness. When touched, every branchlet above the shock emits a phosphoric glow, while all the polyps beneath remain in darkness. When thrown into fresh water or alcohol, they scatter sparks about in all directions, a most beautiful sight; dying, as it were, in a halo of glory.
But of all the marine animals the Pyrosomas, doing full justice to their name (fire-bodies) seem to emit the most vivid coruscations. Bibra relates in his "Travels to Chili" that he once caught half a dozen of these remarkable light-bearers, by whose phosphorescence he could distinctly read their own description in a naturalist's vade-mecum. Although completely dark when at rest the slightest touch sufficed to elicit their clear blue-green light. During a voyage to India, Mr. Bennett had occasion to admire the magnificent spectacle afforded by whole shoals of Pyrosomas. The ship, proceeding at a rapid rate, continued during an entire night to pass through distinct but extensive fields of these molluscs, floating and glowing as they floated on all sides of her course. Enveloped in a flame of bright phosphorescent light, and gleaming with a greenish lustre, the Pyrosomes, in vast sheets, upwards of a mile in breadth, and stretching out till lost in the distance, presented a sight, the glory of which may be easily imagined. The vessel, as it cleaved the gleaming mass, threw up strong flashes of light, as if ploughing through liquid fire, which illuminated the hull, the sails, and the ropes, with a strange unearthly radiance.
In his memoir on the Pyrosoma, M. Péron describes with lively colours the circumstances under which he first made its discovery, during a dark and stormy night, in the tropical Atlantic. "The sky," says this distinguished naturalist, "was on all sides loaded with heavy clouds; all around the obscurity was profound; the wind blew violently, and the ship cut her way with rapidity. Suddenly we discovered at some distance a great phosphorescent band stretched across the waves, and occupying an immense tract in advance of the ship. Heightened by the surrounding circumstances, the effect of this spectacle was romantic, imposing, sublime, rivetting the attention of all on board. Soon we reached the illuminated tract, and perceived that the prodigious brightness was certainly and only attributable to the presence of an innumerable multitude of largish animals floating with the waves. From their swimming at different depths they took apparently different forms: those at the greatest depth were very indefinite, presenting much the appearance of great masses of fire, or rather of enormous red-hot cannon balls; whilst those more distinctly seen near the surface perfectly resembled incandescent cylinders of iron.
"Taken from the water, these animals entirely resembled each other in form, colour, substance, and the property of phosphorescence, differing only in their sizes, which varied from three to seven inches. The large, longish tubercles with which the exterior of the Pyrosomes was bristled were of a firmer substance, and more transparent than the rest of the body, and were brilliant and polished like diamonds. These were the principal scene of phosphorescence. Between these large tubercles, smaller ones, shorter and more obtuse, could be distinguished; these also were phosphorescent. Lastly, in the interior of the substance of the animal, could be seen, by the aid of the transparency, a number of little, elongated, narrow bodies (viscera), which also participated in a high degree in the possession of the phosphoric light."
In the Pholades or Lithodomes, that bore their dwellings in the hard stone, as other shell-fish do in the loose sands, the whole mass of the body is permeated with light. Pliny gives us a short but animated description of the phenomenon in the edible date-shell of the Mediterranean (Pholas dactylus):—
"It is in the nature of the pholades to shine in the darkness with their own light, which is the more intense as the animal is more juicy. While eating them, they shine in the mouth and on the hands, nay, even the drops falling from them upon the ground continue to emit light, a sure proof that the luminosity we admire in them is associated with their juice." Milne-Edwards found this observation perfectly correct, for wishing to place some living pholades in alcohol, he saw a luminous matter exude from their bodies, which on account of its weight sank in the liquid, covering the bottom of the vessel, and there forming a deposit as shining as when it was in contact with the air.
Several kinds of fishes likewise possess the luminous faculty. The sun-fish, that strange deformity, emits a phosphoric gleam; and a species of Gurnard (Trigla lucerna) is said to sparkle in the night, so as to form fiery streams through the water.
With regard to the luminosity of the larger marine animals, Ermann, however, remarks that he so often saw small luminous crustacea in the abdominal cavity of the transparent Salpa pinnata, that it may well be asked whether the phosphorescence of the larger creatures is not in reality owing to that of their smaller companions.
According to Mr. Bennett, "Whaling Voyage round the Globe," a species of shark first discovered by himself is distinguished by an uncommonly strong emission of light. When the specimen, taken at night, was removed into a dark apartment, it afforded a very interesting spectacle. The entire inferior surface of the body and head emitted a vivid and greenish phosphorescent gleam, imparting to the creature by its own light a truly ghastly and terrific appearance. The luminous effect was constant, and not perceptibly increased by agitation or friction. When the shark expired, (which was not until it had been out of the water more than three hours,) the luminous appearance faded entirely from the abdomen, and more gradually from other parts; lingering longest around the jaws and on the fins.
The only part of the under surface of the animal which was free from luminosity was the black collar round the throat; and while the inferior surface of the pectoral, anal, and caudal fins shone with splendour, their superior surface (including the upper lobe of the tail fin) was in darkness, as were also the dorsal fins, and the back and summit of the head.
Mr. Bennett is inclined to believe that the luminous power of this shark resides in a peculiar secretion from the skin. It was his first impression that the fish had accidentally contracted some phosphorescent matter from the sea, or from the net in which it was captured; but the most rigid investigation did not confirm this suspicion, while the uniformity with which the luminous gleam occupied certain portions of the body and fins, its permanence during life, and decline and cessation upon the approach and occurrence of death, did not leave a doubt in his mind but that it was a vital principle essential to the economy of the animal. The small size of the fins would appear to denote that this fish is not active in swimming; and, since it is highly predaceous and evidently of nocturnal habits, we may perhaps indulge in the hypothesis, that the phosphorescent power it possesses is of use to attract its prey, upon the same principle as the Polynesian islanders and others employ torches in night-fishing.
Some of the lower sea-plants also appear to be luminous. Thus, over a space of more than 600 miles (between lat. 8° N. and 2° S.), Meyen saw the ocean covered with phosphorescent Oscillatoria, grouped together into small balls or globules, from the size of a poppy-seed to that of a lentil.
But if the luminosity of the ocean generally proceeds from living creatures, it sometimes also arises from putrefying organic fibres and membranes, resulting from the decomposition of those living light-bearers. "Sometimes," says Humboldt, "even a high magnifying power is unable to discover any animals in the phosphorescent water, and yet light gleams forth wherever a wave strikes against a hard body and dissolves in foam. The cause of this phenomenon lies then most likely in the putrefying fibres of dead mollusks, which are mixed with the waters in countless numbers."
Summing up the foregoing in a few words, it is thus an indisputable fact, that the phosphorescence of the sea is by no means an electrical or magnetic property of the water, but exclusively bound to organic matter, living or dead. But although thus much has been ascertained, we have as yet only advanced one step towards the unravelling of the mystery, and its proximate cause remains an open question. Unfortunately, science is still unable to give a positive answer, and we are obliged to be contented with a more or less plausible hypothesis. When we consider that the phosphorescence most commonly resides only in the outward mucous covering of the body, in which a number of particles cast off by the skin are continually undergoing decomposition, the phenomenon seems to be a simple chemical process, during which more or less phosphorus may be disengaged, which by agitation or friction gives rise to the emission of light. It is more difficult to explain those cases in which the entire mass of the body is luminous (as in Pholas), or the muscular substance (as in some Annelides), or the vibratory cilia (as in the Beroës); and here we do better to confess our entire ignorance, than to resort to the hypothesis of electrical discharges, extremely improbable in an element which is so excellent an electrical conductor, and particularly when we consider that no emission of light takes place in the few and powerful electrical fishes we are acquainted with.
We know as little of what utility marine phosphorescence may be. Why do the countless myriads of Mammariæ gleam and sparkle along our coasts? Is it to signify their presence to other animals, and direct them to the spot where they may find abundance of food? So much is certain, that so grand and wide-spread a phenomenon must necessarily serve some end equally grand and important.
As the phosphorescence of the sea is owing to living creatures, it must naturally show itself in its greatest brilliancy when the ocean is at rest; for during the daytime we find the surface of the waters most peopled with various animals when only a slight zephyr glides over the sea. In stormy weather, the fragile or gelatinous world of the lower marine creatures generally seeks a greater depth, until the elementary strife has ceased, when it again loves to sport in the warmer or more cheerful superficial waters.
In the tropical zone, Humboldt saw the sea most brilliantly luminous before a storm, when the air was sultry, and the sky covered with clouds. In the North Sea we observe the phenomenon most commonly during fine tranquil autumnal nights; but it may be seen at every season of the year, even when the cold is most intense. Its appearance is, however, extremely capricious; for, under seemingly unaltered circumstances, the sea may one night be very luminous, and the next quite dark. Often months, or even years, pass by without witnessing it in full perfection. Does this result from a peculiar state of the atmosphere, or do the little animals love to migrate from one part of the coast to another?
It is remarkable that the ancients should have taken so little notice of oceanic phosphorescence. The "Periplus" of Hanno contains perhaps the only passage in which the phenomenon is described. To the south of Cerne the Carthaginian navigator saw the sea burn, as it were, with streams of fire. Pliny, in whom the miracle (miraculum, as he calls it) of the date-shell excited so lively an admiration, and who must often have seen the sea gleam with phosphoric light, as the passage proves where he mentions in a few dry words the luminous gurnard (lucerna) stretching out a fiery tongue, has no exclamation of delight for one of the most beautiful sights in nature. Homer also, who has given us so many charming descriptions of the sea in its ever-changing aspects, and who so often leads us with long-suffering Ulysses through the nocturnal floods, never once makes them blaze or sparkle in his immortal hexameters.
Even modern poets mention the phenomenon but rarely. Camoens himself, whom Humboldt, on account of his beautiful oceanic descriptions, calls, above all others, the "poet of the sea," forgets to sing it in his Lusiad. Byron in his "Corsair" has a few lines on the subject:
but contents himself, as we see, with coldly mentioning a phenomenon so worthy of all a poet's enthusiasm. In Coleridge's wondrous ballad of "The ancient Mariner" we find a warmer description:
These indeed are lines whose brilliancy emulates the splendour of the phenomenon they depict, but even they are hardly more beautiful than Crabbe's admirable description:
Or than the graphic numbers of Sir Walter Scott:
THE PRIMITIVE OCEAN.
The greatest of all histories, traced in mighty characters by the Almighty himself, is that of the earth-rind. The leaves of this giant volume are the strata which have been successively deposited in the bosom of the sea, or raised by volcanic powers from the depths of the earth; the wars which it relates are the Titanic conflicts of two hostile elements, water and fire, each anxious to destroy the formations of its opponent; and the historic documents which bear witness to that ancient strife lie before us in the petrified or carbonified remains of extinct forms of organic existence—the medals of creation.
It is only since yesterday that science has attempted to unriddle the hieroglyphics in which the past history of our planet reveals itself to man, and it stands to reason that in so difficult a study truth must often be obscured by error; but although the geologist is still a mere scholar, endeavouring to decipher the first chapters of a voluminous work, yet even now the study of the physical revolutions of our globe distinctly points out a period when the molten earth wandered, a ball of liquid fire, through the desert realms of space. In those times, so distant from ours that even the wildest flight of imagination is unable to carry us over the intervening abyss, the waters of the ocean were as yet mixed with the air, and formed a thick and hazy atmosphere through which no radiant sunbeam, no soft lunar light, ever penetrated to the fiery billows of molten rock, which at that time covered the whole surface of the earth. What pictures of desolation rise before our fancy, at the idea of yon boundless ocean of fluid stone, which rolled from pole to pole without meeting on its wide way anything but itself. Ever and ever in the dark-red clouds shone the reflection of that vast conflagration, witnessed only by the eye of the Almighty, for organic life could not exist on a globe which exclusively obeyed the physical and chemical laws of inorganic nature.
But while the fiery mass with its surrounding atmosphere was circling through the icy regions of ethereal space (the temperature of which is computed to be lower than 60° R. below freezing point), it gradually cooled, and its hitherto fluid surface began to harden to a solid crust. Who can tell how many countless ages may have dropped one after the other into the abyss of the past, ere thus much was accomplished; for the dense atmosphere constantly threw back again upon the fiery earth-ball the heat radiating from its surface, and the caloric of the vast body could escape but very slowly into vacant space?
Thus millions of years may have gone by before the aqueous vapours, now no longer obstinately repelled by the cooling earth-rind, condensed into rain, and, falling in showers, gave birth to an incipient ocean. But it must not be supposed that the waters obtained at once a tranquil and undisturbed possession of their new domain, for, as soon as they descended upon the earth, those endless elementary wars began, which, with various fortunes, have continued to the present day.
As soon as the cooling earth-rind began to harden, it naturally contracted, like all solid bodies when no longer subject to the influence of expanding heat, and thus in the thin crust enormous fissures and rents were formed, through which the fluid masses below gushed forth, and, spreading in wide sheets over the surface, once more converted into vapours the waters they met with in their fiery path.
But after all these revolutions and vicissitudes which opposed the birth of ocean, perpetually destroying its perpetually renewed formation, we come at last to a period when, in consequence of the constantly decreasing temperature of the earth-rind, and its increasing thickness, the waters at last conquered a permanent abode on its surface, and the oceanic empire was definitively founded.
The scene has now changed; the sea of fire has disappeared, and water covers the face of the earth. The rind is still too thin, and the eruptions from below are still too fluid to form higher elevations above the general surface: all is flat and even, and land nowhere rises above the mirror of a boundless ocean.
This new state of things still affords the same spectacle of dreary uniformity and solitude in all its horrors. The temperature of the waters is yet too high, and they contain too many extraneous substances, too many noxious vapours arise from the clefts of the earth-rind, the dense atmosphere is still too much impregnated with poisons, to allow the hidden germs of life anywhere to awaken. A strange and awful primitive ocean rises and falls, rolls and rages, but nowhere does it beat against a coast; no animal, no plant, grows and thrives in its bosom; no bird flies over its expanse.
But meanwhile the hidden agency of Providence is unremittingly active in preparing a new order of things. The earth-rind increases in thickness, the crevices become narrower, and the fluid or semi-fluid masses escaping through the clefts ascend to a more considerable height.
Thus the first islands are formed, and the first separation between the dry land and the waters takes place. At the same time no less remarkable changes occur, as well in the constitution of the waters as in that of the atmosphere. The farther the glowing internal heat of the planet retires from the surface, the greater is the quantity of water which precipitates itself upon it. The ocean, obliged to relinquish part of its surface to the dry land, makes up for the loss of extent by an increase of depth, and the clearer atmosphere allows the enlivening sunbeam to gild here the crest of a wave, there a naked rock.
And now also life awakens in the seas, but how often has it changed its forms, and how often has Neptune displaced his boundaries since that primordial dawn. Alternately rising or subsiding, what was once the bottom of the ocean now forms the mountain crest, and whole islands and continents have been gradually worn away and whelmed beneath the waves of the sea, to arise and to be whelmed again. In every part of the world we are able to trace these repeated changes in the fossil remains embedded in the strata that have successively been deposited in the sea, and then again raised above its level by volcanic agencies, and thus, by a wonderful transposition, the history of the primitive ocean is revealed to us by the tablets of the dry land. The indefatigable zeal of the geologists has discovered no less than thirty-nine distinct fossiliferous strata of different ages, and as many of these are again subdivided into successive layers, frequently of a thickness of several thousand feet, and each of them characterised by its peculiar organic remains, we may form some idea of the vast spaces of time required for their formation.
The annals of the human race speak of the rise and downfall of nations and dynasties, and stamp a couple of thousand years with the mark of high antiquity; but each stratum or each leaf in the records of our globe has witnessed the birth and the extinction of numerous families, genera, and species of plants and animals, and shows us organic Nature as changeable in time as she appears to us in space. As, when we sail to the southern hemisphere, the stars of the northern firmament gradually sink below the horizon, until finally entirely new constellations blaze upon us from the nightly heavens; thus in the organic vestiges of the palæozoic seas we find no form of life resembling those of the actual times, but every class
Then spiral-armed Brachiopods were the chief representatives of the molluscs; then crinoid star-fishes paved the bottom of the ocean; then the fishes, covered with large thick rhomboidal scales, were buckler-headed like the Cephalaspis, or furnished with wing-like appendages like the Pterichthys; and then the Trilobites, a crustacean tribe, thus named from its three lobed skeleton, swarmed in the shallow littoral waters where the lesser sea-fry afforded them an abundant food. From a comparison of their structure with recent analogies, it is supposed that these strange creatures swam in an inverted position close beneath the surface of the water, the belly upwards, and that they made use of their power of rolling themselves into a ball as a defence against attacks from above. The remains of seventeen families of Trilobites, including forty-five genera and 477 species, some of the size of a pea, others two feet long, testify the once flourishing condition of these remarkable crustaceans, yet but few of their petrified remains, so numerous in the Silurian and Devonian strata, are found in the carboniferous or mountain limestone, and none whatever in formations of more recent date. Thus, long before the wind ever moaned through the dense fronds of the tree ferns and calamites which once covered the swampy lowlands of our isle, and long before that rich vegetation began, to which we are indebted for our inexhaustible coal-fields, now frequently buried thousands of feet below the surface on which they originally grew, the Trilobites belonged already to the things of the past!
In the seas of the mesozoic or mediæval period, new forms of life appear upon the scene. A remarkable change has taken place in the cephalopods; for the chambered and straightened Orthoceratites and many other families of the order have passed away, and the spiral Ammonites, branching out into numerous genera, and more than 600 species, now flourish in the seas, so that in some places the rocks seem, as it were, composed of them alone. Some are of small dimensions, others upwards of three feet in diameter. They are met with in the Alps, and have been found in the Himalaya Mountains, at elevations of 16,000 feet, as eloquent witnesses of the vast revolutions of which our earth has been the scene. Carnivorous, and resembling in habits the Nautili, their small and feeble representatives of the present day, their immense multiplication proves how numerous must have been the molluscs, crustaceans, and annelides, on which they fed, all like them widely different from those of the present day.
Then also flourished the Belemnites (Thunder-stones), supposed by the ancients to be the thunderbolts of Jove, but now known to be the petrified internal bones of a race of voracious ten-armed cuttle-fishes, whose importance in the oolitic or cretaceous seas may be judged of by the frequency of their remains, and the 120 species that have been hitherto discovered. Belemnites two feet long have been found, so that, to judge by analogies, the animals to which they belonged as cuttle-bones must have measured eighteen or twenty feet from end to end, a size which reduces the rapacious Onychoteuthis of the present seas to dwarfish dimensions.
But of all the denizens of the mesozoic seas none were more formidable than the gigantic Saurians, whose approach put even the voracious sharks to flight. The first of these monsters that raises its frightful head above the waters is the dreadful Ichthyosaurus, a creature thirty or even fifty feet long, half fish, half lizard, and combining in strange assemblage the snout of the porpoise, the teeth of the crocodile, and the paddles of the whale. Singular above all is the enormous eye, in size surpassing a man's head. Woe to the fish that meets its appalling glance! No rapidity of flight, no weapon, be it sword or saw, avails, for the long-tailed gigantic saurian darts like lightning through the water, and its dense harness bids defiance to every attack. Not only have fifteen distinct species of Ichthyosauri been distinguished, but the remains of crushed and partially digested fish-bones and scales, which are found within their skeleton, indicate the precise nature of their food. Their fossil remains abound along the whole extent of the lias formation, from the coasts of Dorset, through Somerset and Leicestershire to the coast of Yorkshire, but the largest specimens have been found in Franconia.
Along with this monster, another and still more singular deformity makes its appearance, the Plesiosaurus, in which the fabulous chimæras and hydras of antiquity seem to start into existence. Fancy a crocodile twenty-seven feet long, with the fins of a whale, the long and flexible neck of a swan, and a comparatively small head. With the appearance of this new tyrant, the last hope of escape is taken from the trembling fishes; for into the shallow waters, inaccessible to the more bulky Ichthyosaurus, the slender Plesiosaurus penetrates with ease.
A race of such colossal powers seemed destined for an immortal reign, for where was the visible enemy that could put an end to its tyranny? But even the giant strength of the saurians was obliged to succumb to the still more formidable power of all-changing time, which slowly but surely modified the circumstances under which they were called into being, and gave birth to higher and more beautiful forms.
In the tertiary period, the dreadful reptiles of the mesozoic seas have long since vanished from the bosom of the ocean, and cetaceans, walruses, and seals, unknown in the primitive deep, now wander through the waters or bask on the sunny cliffs. With them begins a new era in the life of the sea. Hitherto it has only brought forth creatures of base or brutal instinct, but now the Divine spark of parental affection begins to ennoble its more perfect inhabitants, and to point out the dim outlines of the spiritual world.
During all these successive changes the surface of the earth has gradually cooled to its present temperature, and many plants and animals that formerly enjoyed the widest range must now rest satisfied with narrower limits. The sea-animals of the north find themselves for ever severed from their brethren of the south, by the impassable zone of the tropical ocean; and all the fishes, molluscs, and zoophytes, whose organisation requires a greater warmth, confine themselves to the equatorial regions.
As the tertiary period advances towards the present epoch, the species which flourished in its prime become extinct, like the numberless races which preceded them; new modifications of life, more and more similar to those of the present day, start into existence; and, finally, creation appears with increasing beauty in her present rich attire.
Thus old Ocean, after having devoured so many of his children, has transformed himself at last into our contemporaneous seas, with their currents and floods, and the various animals and plants growing and thriving in their bosom.
Who can tell when the last great revolutions of the earth-rind took place, which, by the upheaving of mighty mountains or the disruption of isthmuses, drew the present boundaries of land and sea? or who can pierce the deep mystery which veils the future duration of the existing phase of planetary life?
So much is certain, that the ocean of the present day will be transformed as the seas of the past have been, and that "all that it inhabit" are doomed to perish like the long line of animal and vegetable forms which preceded them.
We know by too many signs that our earth is slowly but unceasingly working out changes in her external form. Here lands are rising, while other areas are gradually sinking; here the breakers perpetually gnaw the cliffs, and hollow out their sides, while in other places alluvial deposits encroach upon the sea's domain.
However slowly these changes may be going on, they point to a time when a new ocean will encircle new lands, and new animal and vegetable forms arise within its bosom. Of what nature and how gifted these races yet slumbering in the lap of time may be, He only knows whose eye penetrates through all eternity; but we cannot doubt that they will be superior to the present denizens of the ocean.
Hitherto the annals of the earth-rind have shown us uninterrupted progress; why, then, should the future be ruled by different laws? At first the sea only produces weeds, shells, crustacea; then the fishes and reptiles appear; and the cetaceans close the vista. But is this the last word, the last manifestation of oceanic life, or is it not to be expected that the future seas will be peopled with beings ranking as high above the whale or dolphin as these rank above the giant saurians of the past?
Among the nations of antiquity, navigation, as may well be supposed, was in a very rude and imperfect state. Unacquainted with the mariner's compass, which during the darkest and most tempestuous nights safely leads the modern seaman over the pathless ocean, the sparkling constellations of a serene sky, or the position of the sun, were the only guides of the ancient navigator. He therefore rarely ventured to lose sight of land, but cautiously steering his little bark along the shore, was subject to all the delays and dangers of coast navigation. Even under the mild sky and in the calm waters of the Mediterranean, it was only during the summer months that he dared to leave the port; to brave the fury of the wintry winds was a boldness he never could have thought of. Under such adverse circumstances, it is surely far less astonishing that the geographical knowledge of the ancients was so extremely limited when compared with ours, than that with means so scanty they yet should have known so much of the boundaries of ocean.
But the spirit of commercial enterprise triumphs over every difficulty. Stimulated by the love of gain, and the hope of discovering new sources of wealth, the Phœnicians, the first great maritime nation mentioned in history, were continually enlarging the limits of the known earth, until the fatal moment when the sword of the conqueror destroyed their cities, and extinguished their power for ever.
The first periods of Phœnician greatness are veiled in the mysterious darkness of an unknown past, yet so much is certain, that their date must have been very remote; as, according to the accounts which Herodotus received from the priests, the foundation of Tyre took place thirty centuries before the Christian era.
Long before the expedition of the Argonauts, the Phœnicians had already founded colonies on the Bithynian coast of the Black Sea (Pronectus, Bithynium); and that at a very early time they must have steered through the Straits of Grades into the Atlantic is proved by the fact, that, as far back as the eleventh century before Christ, they founded the towns of Grades and Tartessus on the western coast of Southern Spain. Penetrating farther and farther to the north, they discovered Britain, where they established their chief station on the Scilly Isles, at present so insignificant and obscure, and even visited the barbarous shores of the Baltic in quest of the costly amber. They planted their colonies along the north-west coast of Africa, even beyond the tropic; and, 2000 years before Vasco de Gama, Phœnician mariners are said to have circumnavigated that continent, for Herodotus relates that a Tyrian fleet, fitted out by Necho II., Pharaoh of Egypt (611-595 B.C.), sailed from a port in the Red Sea, doubled the southern promontory of Africa, and, after a voyage of three years, returned through the Straits of Grades to the mouth of the Nile.
Less wonderful, but resting on better historical proof, is the celebrated voyage of discovery to the south which Hanno performed by command of the senate of Carthage, the greatest of all Phœnician colonies, eclipsing even the fame of Tyre itself. Sailing from Cerne, the principal Phœnician settlement on the western coast of Africa, and which was probably situated on the present island of Arguin, he reached, after a navigation of seventeen days, a promontory which he called the West Horn (probably Cape Palmas), and then advanced to another cape, to which he gave the name of South Horn, and which is manifestly Cape de Tres Puntas, only 5° north of the line. During daytime the deepest silence reigned along the newly discovered coast, but after sunset countless fires were seen burning along the banks of the rivers, and the air resounded with music and song, the black natives spending, as they still do now, the hours of the cool night in festive joy. Most likely the Canary Islands were also known to the Phœnicians, as the summit of the Peak of Teneriffe is visible from the heights of Cape Bojador.
The progress of the great mariners of old in the Indian Ocean was no less remarkable than the extension of their Atlantic discoveries. Far beyond Bab-el-Mandeb their fleets sailed to Ophir or Supara, and returned with rich cargoes of gold, silver, sandal-wood, jewels, ivory, apes, and peacocks, to the ports of Elath and Ezion-Geber at the head of the Red Sea. These costly productions of the south were then transported across the Isthmus of Suez to Rhinocolura, the nearest port on the Mediterranean, and thence to Tyre, which ultimately distributed them over the whole of the known world.
The true position of Ophir is an enigma which no learned Œdipus will ever solve. While some authorities place it on the east coast of Africa, others fix its situation somewhere on the west coast of the Indian peninsula; and Humboldt is even of opinion that the name had only a general signification, and that a voyage to Ophir meant nothing more than a commercial expedition to any part of the Indian Ocean, just as at present we speak of a voyage to the Levant or the West Indies.
But whatever Ophir may have been, it is certain that the Phœnicians carried on a considerable trade with the lands and nations beyond the Gates of the Red Sea. Their trade in the direction of the Persian Gulf was no less extensive. Through the Syrian desert, where Palmyra, their chief station or emporium, proudly rose above the surrounding sands, their caravans slowly wandered to the banks of the Tigris and Euphrates, to provide Nineveh and Babylon with the costly merchandise of Sidon and Tyre. Following the course of the great Mesopotamian streams, they reached the shores of the Persian Gulf, where they owned the ports of Tylos and Aradus and the rich pearl islands of Bahrein, and, having loaded their empty camels with the produce of Iran and Arabia, returned by the same way to the shores of the Mediterranean. How far their ships may have ventured beyond the mouth of the Persian Gulf is unknown, but the researches of the learned orientalists, Gesenius, Benfey, and Lassen, render it extremely probable, that, taking advantage of the regularly changing monsoons, they sailed through the Straits of Ormus to the coast of Malabar.
The progress of the Phœnician race in the technical arts, as well as in the astronomical and mathematical sciences so highly important for the improvement of their navigation, was no less remarkable for the age in which they lived, than the vast extension of a commercial intercourse which reached from Britain to the Indus, and from the Black Sea to the Senegal. They wove the finest linen, and knew how to dye it with the most splendid purple. They were unsurpassed in the workmanship of metals, and possessed the secret of manufacturing white and coloured glass, which their caravans and ships exchanged for the produce of the north and of the south. By the invention of the alphabet, which with many other useful sciences and arts, they communicated to the Greeks and other nations with whom they traded, they no less contributed to the progress of mankind than by the humanising influence of commerce.
Thus when we consider the services which these merchant-princes of antiquity rendered to their contemporaries, wherever their flag was seen or their caravans appeared, the annihilation of the maritime power of Tyre by Alexander (332 B.C.), and the destruction of Carthage by the Romans (146 B.C.), must strike us as events calamitous to the whole human race. Had the Carthaginians, so distinguished by their commercial spirit and ardour for discovery, triumphed over the semi-barbarous Romans, who, then at least, had not yet learned to imitate the arts of plundered Greece, there is every probability that some Punic Columbus would have discovered America at least a thousand years sooner, and the world at this day be in possession of many secrets still unknown, and destined to contribute to the comforts or enjoyments of our descendants.
In the times of Homer, when the Indian Ocean and the Atlantic had long been known to the Phœnicians, the geographical knowledge of the Greeks was still circumscribed by the narrow limits of the Eastern Mediterranean and part of the Euxine, and many a century elapsed ere their ships ventured beyond the Straits of Gades. Colæus of Samos (639 B.C.) is said to have been the first seafarer of Hellenic race who sailed forth into the Atlantic, compelled by adverse winds, and was able on his return from his involuntary voyage to tell his astonished countrymen of the wondrous rising and falling of the oceanic tides. It was seventy years later before the Phoceans of Massilia, the present Marseilles, ventured to follow the path he had traced out, and to visit the Atlantic port of Tartessus.
The town of Massilia had the additional honour of reckoning among her sons the great traveller Pytheas, the Marco Polo of antiquity. This far-wandering philosopher, who lived about 330 years before Christ, had visited all the coasts of Europe, from the mouths of the Tanais or Don to the shores of Ultima Thule, which, according to Leopold von Buch, was not Iceland, nor Feroë, nor Orcadia, but the Norwegian coast. His narrative first made the Greeks acquainted with North-western Europe, and remained for a long time their only geographical guide to those hyperborean lands.
While the horizon of the Greeks was thus considerably expanding towards the regions of the setting sun, the conquests of Alexander opened to them a new world in the distant Orient. Greek navigators now for the first time unfurled their sails on the Indian Ocean. The Macedonian, desirous not only of subduing Asia but of firmly attaching it to the nations of the Mediterranean by the bonds of mutual interest, and hoping by this means to consolidate his vast conquests, sent a fleet under the command of Nearchus, from the mouths of the Indus to the head of the Persian Gulf, to establish if possible a new road for a regular commercial intercourse between India and Mesopotamia. The performance of this voyage was reckoned by the conqueror one of the most glorious events of his reign, but it may serve as a proof of the slowness of ancient navigation, that Nearchus took ten months to perform a journey which one of our steamers might easily accomplish in five days.
After the disruption of the Macedonian empire, the circle of the Greek discoveries in the Indian Ocean was widened by the enterprising spirit of the Seleucidæ and Ptolemies. Seleucus Nicator is said to have penetrated to the mouths of the Ganges, and the fleets of the Egyptian kings sailed round the peninsula of Hindostan and discovered the coasts of Taprobane or Ceylon, the spicy odours of whose cinnamon-groves are said to be wafted far out to sea, so that—