Physical Geography of the Sea and its Meteorology/Chapter 14
CHAPTER XIV.
§ 580-619. THE BASIN AND BED OF THE ATLANTIC.
580. The wonders of the sea.—The wonders of the sea are as marvellous as the glories of the heavens; and they proclaim, in songs divine, that they too are the work of holy fingers. Among the revelations which scientific research has lately made concerning the crust of our planet, none are more interesting to the student of nature, or more suggestive to the Christian philosopher, than those which relate to the bed and bottom of the ocean.
581. Its bottom and Chimhorazo.—The basin of the Atlantic, according to the deep-sea soundings made by the American and English navies, is shown on Plate XI. This plate refers chiefly to that part of the Atlantic which is included within our hemisphere. In its entire length, the basin of this sea is a long trough separating the Old World from the New, and extending probably from pole to pole. As to breadth, it contrasts strongly with the Pacific Ocean. From the top of Chimborazo to the bottom of the Atlantic, at the deepest place yet reached by the plummet in that ocean, the distance, in a vertical line, is nine miles.
582. An orographic view.—Could the waters of the Atlantic be drawn off so as to expose to view this great sea-gash which separates continents, and extends from the Arctic to the Antarctic, it would present a scene the most rugged, grand, and imposing. The very ribs of the solid earth, with the foundations of the sea, would be brought to light, and we should have presented to us in one view, in the empty cradle of the ocean, "a thousand fearful wrecks," with that array of "dead men's skulls, great anchors, heaps of pearl and inestimable stones," which, in the poet's eye, lie scattered on the bottom of the sea, making it hideous with sights of ugly death. To measure the elevation of the mountain-top above the sea, and to lay down upon our maps the elevated ranges of the earth, is regarded in geography as an important thing, and rightly so. Equally important is it, in bringing the physical geography of the sea regularly within the domains of science, to present its orology, by mapping out the bottom of the ocean so as to show the depressions of the solid parts of the earth's crust there, below the sea-level.
583. Plate XI.—Plate XI. presents the latest attempt at such a map. It relates exclusively to the bottom of that part of the Atlantic Ocean which lies north of 10° south. It is stippled with four shades: the darkest (that which is nearest the shore-line) shows where the water is less than six thousand feet deep; the next, where it is less than twelve thousand feet deep; the third, where it is less than eighteen thousand; and the fourth, or lightest, where it is not over twenty-four thousand feet deep. The blank space south of Nova Scotia and the Grand Banks includes a district within which casts showing very deep water have been reported, but which subsequent investigation and discussion do not appear to confirm. The deepest part of the North Atlantic is probably somewhere between the Bermudas and the Grand Banks, but how deep it may be yet remains for the cannon-ball and sounding-twine to determine. The waters of the Gulf of Mexico are held in a basin about a mile deep in the deepest part. The bottom of the Atlantic, or its depressions below the sea-level, are given, perhaps, on this plate with as much accuracy as the best geographers have been enabled to show, on a map, the elevations above the sea-level of the interior either of Africa or Australia.
584. "Whats the use" of deep-sea soundings?—" What is to be the use of these deep-sea soundings?" is a question that often occurs; and it is as difficult to be answered in categorical terms as Franklin's question, "What is the use of a new-born babe?" Every physical fact, every expression of nature, every feature of the earth, the work of any and all of those agents which make the face of the world what it is, and as we see it, is interesting and instructive. Until we get hold of a group of physical facts, we do not know what practical bearings they may have, though right-minded men know that they contain many precious jewels, which the experts of philosophy will not fail to bring-out, polished and bright, and beautifully adapted, sooner or later, to man's purposes. Already we are obtaining practical answers to this question as to the use of deep-sea soundings; for, as soon as they were announced to the public, they forthwith assumed a practical bearing in the minds of men with regard to the question of a submarine telegraph across the Atlantic.
585. The telegraphic plateau.—There is, at the bottom of this sea, between Cape Race, in Newfoundland, and Cape Clear, in Ireland, a remarkable steppe, which is already known as the telegraphic plateau, and has already been made famous by the attempts to run a telegraphic cable across the ocean upon it. In August, 1858, a cable was laid upon it from Valencia in Ireland to Trinity Bay in Newfoundland, and but a few messages were passed through it, when it ceased to work. Whether messages can ever be successfully sent, in a commercial sense, through such a length of continuous submarine wire, is by no means certain; but that the wires of 1858 so soon ceased to pass any current at all was no doubt owing to the fact that the cable was constructed upon erroneous principles. Its projectors, in planning its construction, did not, unfortunately, avail themselves of the light which our deep-sea soundings had cast upon the bed of the ocean.
586. The first specimens of deep-sea soundings.—It was upon this plateau that Brooke's sounding apparatus brought up its first trophies from the bottom of the sea. These specimens the officers of the Dolphin judged to be clay; but they took the precaution to label them, carefully to preserve them, and, on their return to the United States, to send them to the proper bureau. They were divided; a part was sent for examination to Professor Ehrenberg, of Berlin, and a part to the late Professor Bailey, of West Point—eminent microscopists both. The latter thus responded:—
587. Baileys letter.—"I am greatly obliged to you for the deep soundings you sent me last week, and I have looked at them with great interest. They are exactly what I have wanted to get hold of. The bottom of the ocean at the depth of more than two miles I hardly hoped ever to have a chance of examining; yet,, thanks to Brooke's contrivance, we have it clean and free from grease, so that it can at once be put under the microscope. I was greatly delighted to find that all these deep soundings are filled, with microscopic shells; not a particle of sand or gravel exists in them. They are chiefly made up of perfect little calcareous shells (Foraminifera), and contain, also, a number of silicious shells (Diatomaceæ). It is not probable that these animals lived at the depths where these shells are found, but I rather think that they inhabit the waters near the surface; and when they die, their shells settle to the bottom. With reference to this point, I shall be very glad to examine bottles of water from various depths which were brought home by the Dolphin, and any similar materials, either 'bottom,' or water from other localities. I shall study them carefully. . . . The results already obtained are of very great interest, and have many important bearings on geology and zoology. ... I hope you will induce as many as possible to collect soundings with Brooke's lead, in all parts of the world, so that we can map out the animalculæ. as you have the whales. Get your whalers also to collect mud from pancake ice, etc., in the polar regions; this is always full of interesting microscopic forms."
588. Specimens from the coral sea.—Lieutenant Brooke, of the North Pacific Exploring Expedition, procured specimens of the bottom from the depth of 2150 fathoms in the coral sea, lat. 13° S., long. 162° E. With regard to these, the admirable and lamented Bailey wrote in 1855, "You may be sure I was not backwards in taking a look at the specimens you sent me, which, from their locality, promised to be so interesting. The sounding from 2150 fathoms, although very small in quantity, is not so bad in quality, yielding representatives of most of the great groups of microscopic organisms usually found in marine sediments. The predominant forms are silicious spicules of sponges. Various forms of these occur: some long and spindle-shaped, or acicular; others pin-headed; some three-spined, etc., etc. The Diatomes (silicious. infusoria of Ehrenberg) are very few in number, and mostly fragmentary. I found, however, some perfect valves of a coscinodiscus. The Foraminifera (Polythalamia of Ehrenberg) are very rare, only one perfect shell being seen, with a few fragments of others. The polycistineee are present, and some species of haliomma wore quite perfect. Fragments of other forms of this group indicate that various interesting species might be obtained if we had more of the material. You will see by the above that this deep sounding differs considerably from those obtained in the Atlantic, The Atlantic soundings were almost wholly composed of calcareous shells of the Foraminifera; these, on the contrary, contain very few Foraminifera, and are of a silicious rather than a calcareous nature. This only makes the condition of things in the Northern Atlantic the more interesting."
589. They belong to the animal, not to the vegetable or mineral kingdom.—The first noticeable thing the microscope gives of these specimens is, that nearly all of them are of the animal, few of the mineral or vegetable kingdom. The ocean teems with life, we know. Of the four elements of the old philosophers—fire, earth, air, and water—perhaps the sea most of all abounds with living creatures. The space occupied on the surface of our planet by the different families of animals and their remains seems to be inversely as the size of the individual. The smaller the animal, the greater the space occupied by its remains. Though not invariably the case, yet this rule, to a certain extent, is true, and will, therefore, answer our present purposes, which are simply those of illustration. Take the elephant and his remains, or a microscopic animal and his, and compare them. The contrast, as to space occupied, is as striking as the difference between great and small. The graveyard that would hold the remains of the coral insect is larger than the graveyard that would hold those of the elephant.
590. Quiet reigns in the depth of the sea.—We notice another practical bearing in this group of physical facts that Brooke's apparatus has fished up from the bottom of the deep sea. Bailey, with his microscope (§ 587), could detect scarcely a single particle of sand or gravel among these little mites of shells. They were from the great telegraphic plateau (§ 585), and the inference is that there, if anywhere, the waters of the sea are at rest. There was not motion enough to abrade these very delicate organisms, nor current enough to sweep them about and mix up with them a grain of the finest sand, nor the smallest particle of gravel torn from the loose beds of debris that here and there strew the bottom of the sea. This plateau is not too deep for the wire to sink down and rest upon, yet it is not so shallow that currents, or icebergs, or any abrading force can derange the wire after it is once lodged there.
591. Is there life in them?—As Professor Bailey remarks (§ 587), the animalculæ, whose remains Brooke's lead has brought up from the bottom of the deep sea, probably did not live or die there. They would have had no light there, and, had they lived there, their frail little texture would have been subjected, in its growth, to the pressure of a column of water twelve thousand feet high, equal to the weight of four hundred atmospheres. They probably lived and died near the surface, where they could feel the genial influence of both light and heat, and were buried in the lichen caves below after death.
592. The ocean in a new light.—Brooke's lead and the microscope, therefore, it would seem, are about to teach us to regard the ocean in a new light. Its bosom, which so teems with animal life—its face, upon which time writes no wrinkles, makes no impression, are, it would now seem, as obedient to the great law of change as is any department whatever either of the animal or the vegetable kingdom. It is now suggested that henceforward we should view the surface of the sea as a nursery teeming with nascent organisms, its depths as the cemetery for families of living creatures that out-number the sands on the sea shore for multitude. Where there is a nursery, hard by there will be found also a graveyard; such is the condition of the animal world. But it never occurred to us before to consider the surface of the sea as one wide nursery, its every ripple a cradle, and its bottom one vast burial-place.
593. Levelling agencies.—On those parts of the solid portions of the earth's crust which are at the bottom of the atmosphere, various agents are at work, levelling both upwards and downwards. Heat and cold, rain and sunshine, the winds and the streams, all, assisted by the forces of gravitation, are unceasingly wasting away the high places on the land, and as perpetually filling up the low. But in contemplating the levelling agencies that are at work upon the solid portions of the crust of our planet which are at the bottom of the sea, one is led, at first thought, almost to the conclusion that these levelling agents are powerless there. In the deep sea there are no abrading processes at work; neither frosts nor rains are felt there, and the force of gravitation is so paralyzed there that it cannot use half its power, as on dry land, in tearing the overhanging rock from the precipice and casting it down into the valley below.
594. The offices of animalculæ.—Hitherto we have, in imagination, been disposed to regard the waters of the sea as a great cushion, placed between the air and the bottom of the ocean, to protect and defend it from these abrading agencies of the atmosphere. The geological clock may we thought, strike new periods; its hands may point to era after era; but, so long as the ocean remains in Its basin, so long as its bottom is covered with blue water, so long must the deep furrows and strong contrasts in the solid crust below stand out boldly, rugged, ragged, and grandly. Nothing can fill up the hollows there; no agent now at work, that we know of, can descend into its depths, and level off the floors of the sea. But it now seems that we forgot the myriads of animalculæ that make the surface of the sea sparkle and glow with life: they are secreting from its surface solid matter for the very purpose of filling up those cavities below. These little marine insects build their habitations at the surface, and when they die, their remains, in vast multitudes, sink down and settle upon the bottom. They are the atoms of which mountains are formed—plains spread out. Our marl- beds, the clay in our river-bottoms, large portions of many of the great basins of the earth, even flinty rocks are composed of the remains of just such little creatures as these, which the ingenuity of Brooke has enabled us to fish up from the depth of nearly four miles (two thousand feet) below the sea-level.[1] These Foraminifera, therefore, when living, may have been preparing the ingredients for the fruitful soil of a land that some earthquake or upheaval, in ages far away in the future, may be sent to cast up from the bottom of the sea for man's use.
595. The study of them profitable.—The study of these "sunless treasures," recovered with so much ingenuity from the rich bottom of the sea, suggests new views concerning the physical economy of the ocean. It not only leads us into the workshops of the inhabitants of the sea— showing us through their nurseries and cemeteries, and enabling us to study their economy—but it conducts us into the very chambers of the deep. Our investigations go to show that the roaring waves and the mightiest billows of the ocean repose, not upon hard or troubled beds, but upon cushions of still water; that everywhere at the bottom of the deep sea the solid ribs of the earth are protected, as with a garment, from the abrading action of its currents, and that the cradle of its restless waves is lined by a stratum of water at rest, or so nearly at rest that it can neither wear nor move the lightest bit of drift that once lodges there.
596. The abrasion of currents.—The tooth of running water is very sharp. See how the Hudson has gnawed through the Highlands, and the Niagara cut its way through layer after layer of the solid rock. But what are the Hudson and the Niagara, with all the fresh water-courses of the world, by the side of the Gulf Stream and other great "rivers in the ocean?" And what is the pressure of fresh water upon river-beds in comparison with the pressure of ocean water upon the bottom of the deep sea? It is not so great by contrast as the gutters in the streets are to the cataract. Then why have not the currents of the sea worn its bottom away? Simply because they are not permitted to get down to it. Suppose the currents which we see at and near the surface of the ocean were permitted to extend all the way to the bottom in deep as well as shallow water, let us see what the pressure and scouring force would be where the sea is only 3000 fathoms deep—for in many places the depth is even greater than that. It is equal there, in round numbers, to the pressure of six hundred atmospheres. Six hundred atmospheres, piled up one above the other, would press upon every square foot of solid matter beneath the pile with the weight of 1,296,000 pounds, or 648 tons.
597. Their pressure on the bottom.—The better to comprehend the amount of such a pressure, let us imagine a column of water just one foot square, where the sea is 3000 fathoms deep, to be frozen from the top to the bottom, and that we could then, with the aid of some mighty magician, haul this shaft of ice up, and stand it on one end for inspection and examination. It would be 18,000 feet high; the pressure on its pedestal would be more than a million and a quarter of pounds; and if placed on a ship of 648 tons burden, it would be heavy enough to sink her. There are currents in the sea where it is 3000 fathoms deep, and some of them—as the Gulf Stream—run with a velocity of four miles an hour and even more. Every square foot of the earth's crust at the bottom of a four-knot current 3000 fathoms deep would have no less than 506,880—in round numbers, half a million—of such columns of water daily dragging, and rubbing, and scouring, and chafing over it, under a continuous pressure of 648 tons. What would the bottom of the sea have to be made of to withstand such erosion? Water running with such a velocity, and with the friction upon the bottom which such a pressure would create, would in time wear away the thickest bed, though made of the hardest adamant. Why, then, has not the bottom of the sea been worn away? Why have not its currents cut through the solid crust in which its billows are rocked, and ripped out from the bowels of the earth the masses of incandescent, molten matter which geologists tell us lie pent up and boiling there?
598. Why they cannot chafe it.—If the currents of the sea, with this four-mile velocity at the surface, and this hundreds of tons pressure on the bottom, were permitted to chafe against its bed, the Atlantic, instead of being two miles deep and 3000 miles broad, would, we may imagine, have been long ago cut down into a narrow channel that might have been as the same ocean turned up on edge, and measuring two miles broad and 3000 deep. But had it been so cut, the proportion of land and water surface would have been destroyed, and the winds, for lack of area to play upon, could not have sucked up from the sea vapours for the rains, and the face of the earth would have become as a desert without water. Now there is a reason why such changes should not take place, why the currents should not uproot nor score the deep bed of the ocean, why they should not throw out of adjustment any physical arrangement whatever: because, in the presence of everlasting wisdom, a compass was set upon the face of the deep; because its waters were measured in the hollow of the Almighty hand; because bars and doors were set to stay its proud waves; and because, when He gave to the sea His decree that its waters should not pass His command. He laid the foundations of the world so fast that they should not he removed for ever.
599. What it consists of.—By bringing up specimens from the depth of the ocean, and studying them through the microscope, it has been ascertained that the bed of the ocean is lined with the microscopic remains of its own dead, with marine feculences which lie on the bottom as lightly as gossamer. How frail yet how strong, how light yet how firm are the foundations of the sea! Its waves cannot fret them, its currents cannot wear them, for the bed of the deep sea is protected from abrasion by a cushion of still and heavy water. There it lies—that beautiful arrangement—spread out over the bottom of the deep, and covering its foundations as with a garment, so that they may not be worn. If the currents chafe upon it now here, now there, as in shallow seas they sometimes do, this protecting cushion is self-adjusting; and the moment the unwonted pressure is removed the liquid cushion is restored, and there is again compensation.
600. The causes that produce currents in the sea reside near its surface.—The discovery of this arrangement in the oceanic machinery suggests that the streams of running water in the sea play rather about its surface than in its depths; that the causes which produce currents reside at and near the surface; that these causes are changing heat and alternating cold with their powers of contraction and expansion—winds and sea-shells with evaporation and precipitation; and it is certain that none of these agents appear capable of reaching with their influences very far down into the depths of the great and wide sea. They go not much, if any, farther down than the light can reach. On the other hand, the most powerful agents in the atmosphere reside at and near its bottom; so that, where these two great oceans meet—the aqueous and the aerial—there we probably have the greatest conflict and the most powerful display of the forces that set and keep them in motion, making them to rage and roar.
601. Their depth.—The greatest depth at which running water is to be found in the sea is probably in the narrowest part of the Gulf Stream, as, coming from its mighty fountain, it issues through the Florida Pass. The deep-sea thermometer shows that even here there is a layer of cold water in the depths beneath, so that this "river in the sea" may chafe not against the solid bottom. What revelations of the telescope, what wonders of the microscope, what fact relating to the physical economy of this terrestrial globe, is more beautiful or suggestive than some of the secrets which have been fished up from the caverns of the deep, and brought to light from the hidden paths of the sea?
602. The cushion of still water—its thickness.—In my researches I have as yet found no marks of running water impressed upon the foundations of the sea beyond the depth of two or three thousand feet. Should future deep-sea soundings establish this as a fact in other seas also, it will prove of the greatest value to submarine telegraphy. What may be the thickness of this cushion of still water that covers the bottom of the deep sea is a question of high interest, but we must leave it for future investigation.
603. The conservators of the sea.—In Chapter X. (The Salts of the Sea), I have endeavoured to show how sea-shells and marine insects, may, by reason of the offices which they perform, be regarded as compensations in that exquisite system of physical machinery by which the harmonies of nature are preserved. But the treasures of the lead and revelations of the microscope present the insects of the sea in a new and still more striking-light. We behold them now, serving not only as compensations by which the motions of the water in its channels of circulation are regulated and climates softened, but acting also as checks and balances by which the equipoise between the solid and the fluid matter of the earth is preserved. Should it be established that these microscopic creatures live at the surface, and are only buried at the bottom of the sea, we may then view them as conservators of the ocean; for, in the offices which they perform, they assist to preserve its status by maintaining the purity of its waters.
604. The anti-biotic view the most natural.—Does any portion of the shells which Brooke's sounding-rod brings up from the bottom of the deep sea live there; or are they all the remains of those that lived near the surface in the light and heat of sun, and were buried at the bottom of the deep after death? Philosophers are divided in opinion upon this subject. The facts, as far as they go, seem at first to favour the one conjecture nearly as well as the other. Under these circumstances, I incline to the anti-biotic hypothesis, and chiefly because it would seem to conform better with the Mosaic account of creation. The sun and moon were set in the firmament before the waters were commanded to bring forth the living creature; and hence we infer that light and heat are necessary to the creation and preservation of marine life; and since the light and heat of the sun cannot reach to the bottom of the deep sea, my own conclusion, in the absence of positive evidence upon the subject, has been, that the habitat of those mites of things hauled up from the bottom of the great deep is at and near the surface. On the contrary, others maintain, and perhaps with equal reason, the biotic side of the question. Professor Ehrenberg, of Berlin, is of this latter class.
605. The question stated.—This is an interesting question. It is a new one; and it belongs to that class of questions which mere discussion helps to settle. It is therefore desirable to state both sides—present all the known facts; and then, provided with such lights as they afford, we may draw conclusions.
606. The arguments of the biotics.—As soon as the deep-sea specimens were mounted on the slides of the microscope, the two great masters of that instrument in Europe and America—Bailey of West Point, and Ehrenberg of Berlin—discovered the greater part of the small calcareous carapaces to be filled with a soft pulp, which both admitted to be fleshy matter. From this fact the German argued that there is life at the bottom of the deep sea; the American (§ 587), that there is only death and repose there.
607. Ehrenherg's statement of them.—"The other argument," says Ehrenberg, "for life in the deep which I have established is the surprising quantity of new forms which are wanting in other parts of the sea. If the bottom were nothing but the sediment of the troubled sea, like the fall of snow in the air, and if the biolithic curves of the bottom were nothing else than the product of the currents of the sea which heap up the flakes, similarly to the glaciers, there would necessarily be much less of unknown and peculiar forms in the depths. The surface and the borders of the sea are much more productive and much more extended than the depths ; hence the forms peculiar to the depths should not be perceived. The great quantity of peculiar forms and of soft bodies existing in the innumerable carapaces, accompanied by the observation of the number of unknowns, increasing with the depths—these are the arguments which seem to me to hold firmly to the opinion of stationary life at the bottom of the deep sea."
608. The anti-biotic view.—The anti-biotics, on the other hand, quoted the observations of Professor Forbes, who has shown that, the deeper you go in the littoral waters of the Mediterranean, the fewer are the living forms.
609. Their arguments hosed on the tides.—As for the number of unknowns increasing with the depth (§ 607), they contend that the tides, the currents, and the agitation of the waves all reach to the bottom in shallow water; that they sweep and scour from it the feculences of the sea, as these insect remains may be called, and bear them off into deep water. After reaching a certain depth, then this sediment passes into the stratum of quiet waters that underlie the roaring waves and tossing currents of the surface, and through this stratum these organic remains slowly find their way to the final place of repose as ooze at the bottom of the deep sea. Through such agencies the ooze of the deep sea ought, said the anti-biotics, to be richer than that of shallow water with infusorial remains; mud and all the light sedimentary-matter of river waters are deposited in the deep pools, and not in the shoals and rapids of our fresh-water streams; so we ought, reasoned they of this school, to have the most abundant deposits at the bottom of the deep sea.
610. On the antiseptic properties of sea water.—The anti-biotics referred to the antiseptic properties of sea water, and told how it is customary with mariners, especially with the masters of the sailing packets between Europe and America, to "corn" fresh meat by sinking it to great depths overboard. If they sink it too deep, or let it stay down too long, it becomes too salt. According to them, this process is so quick and thorough, because of the pressure and the affinity which not only forces the water among the fibres of the meat, but which also induces the salt to leave the water and strike into the meat ; and that the fleshy part of these microscopic organisms have been exposed to powerful antiseptic agents is proved by the fact that they are brought up in the middle of the ocean, and remain on board the vessel exposed to the air for months before they reach the hands of the microscopist; some of them have remained so exposed for more than a year, and then been found full of fleshy matter: a sure proof that it had been preserved from putrefaction and decay by processes which it had undergone in the sea, and before it was brought up into the air.
611. On pressure.—Thus the anti-biotics held that these little creatures were preserved for a while after death, and until they reached a certain depth, by salt, and afterwards by pressure. They held that certain conditions are requisite in order that the decay of organic matter may take place; that the animal tissues of these shells during the process of decay are for the most part converted into gases; that these gases, in separating from the animal compound, are capable of exerting only a certain mechanical force, and no more; that this force is not very great; and, unless it were sufficient to overcome the pressure of deep-sea water, their separation could not go on, and that, consequently, there is a certain depth in the sea beyond which animal decomposition or vegetable decay cannot take place. In support of this view, they referred to the well-known effects of pressure in arresting or modifying the energies displayed by certain chemical affinities; and in proof of the position that great compression in the sea prevents putrefaction, they referred to the fact well-known to the fishermen of Nantucket and New Bradford, viz., that when a whale that they have killed sinks in shallow water, he, as the process of decay commences, is seen to swell and rise; but when he sinks in deep water, the pressure is such as to prevent the formation of the distending gases, and he never does rise. Some of these specimens have come from depths where the pressure is equal to that of 400 or 500 atmospheres. Specimens have been obtained by Lieutenant Brooke, in the Pacific, with "fleshy parts" among them, at the depth of 3300 fathoms, and where the pressure is nearly 700 atmospheres. We have brought up fleshy matter from the deep sea as deep down as we have gone; and we may infer that if we were to go to 4000 fathoms, we should still find pulpy matter among the dead organisms there. At that depth, or a little over, common air, according to "Mariotte's law" would be heavier than water, and an air-bubble down there, if any one may imagine such a thing, would be heavy enough to sink. Under such conditions, and with the antiseptic agencies of the sea, the fleshy matter of these infusoria might be preserved at the bottom of the deep sea for a great length of time.
612. Arguments from the Bible.—Moreover (§ 604), the anti-biotics pointed to the first chapter of Genesis to show that light and heat were ordained before the waters were commanded to bring forth. Hence they maintained that light and heat are necessary to marine life. In the depth of the sea there is neither light nor heat, wherefore they brought in circumstantial evidence from the Bible to sustain them in their view.
613. A plan for solving the question.—This was an exceedingly interesting question, and we could suggest but one way of deciding it, which was this: Many of these little organisms of the sea are in the shape of plano-convex discs; all such, when alive, live with the convex side up, the flat side down; but when placed dead in the water and allowed freely to sink, the force of gravity always, and for obvious reasons, causes all such forms to sink with the convex side down. Brooke's lead will bring up these shells exactly as they lie on the bottom, and so he proposed to observe with regard to their manner of lying. Of course, if they lived at the bottom, they would die as they lived, and lie as they died, for (§ 590) there is nothing to turn them over after death at the bottom of the deep sea, consequently their skeletons would be brought' up in the quills of the sounding machine flat side down, convex side up; but if they lived near the surface, and reached the bottom after death, they would be found flat side up.
614. An unexpected solution afforded.—But, before there was an opportunity of trying this plan, Ehrenberg himself afforded the solution in a most unexpected way:—in examining soundings from a great depth in the Mediterranean, he found many fresh-water shells with their fleshy parts still in them, though the specimens were taken from the middle of that sea. That savant, with his practised eye, detected among them Swiss forms, which must have come down the Danube, and so out into the Mediterranean hundreds of miles, and on journeys which would require months, if not years, for these slowly-drifting creatures to accomplish. And so the anti-biotics maintain (§ 603) that their doctrine is established.[2] 615. A discovery suggested by it.—Having thus discovered that the most frail and delicate organisms of the sea can remain in its depths for an indefinite length of time without showing a single trace of decay, we find ourselves possessed of a fact which suggests many beautiful fancies, some touching thoughts, and a few useful ideas; and among these last are found reasons for the conjecture that the gutta percha or other insulating material in which the conducting wires of the sub-Atlantic telegraph and other deep-sea lines are incased, becomes, when lodged beyond a certain depth, impervious to the powers of decay; that, with the weight of the sea upon them, the destructive agents which are so busy upon organic matter in the air and near the surface cannot find room for play. Curious that destruction and decay should be imprisoned and rendered inoperative at the bottom of the great deep!
616. Specimens of the three oceans all tell the same story.—Specimens of the "ooze and bottom of the sea" have also been obtained by the ingenuity of Brooke from the depth of 2700 fathoms in the North Pacific, and examined by Professor Bailey.[3] We have now had specimens from the bottom of "blue water" in the narrow Coral Sea, the broad Pacific, and the long Atlantic, and they all tell the same story, namely, that the bed of the ocean is a vast cemetery. The ocean's bed has been found everywhere, wherever Brooke's sounding-rod has touched, to be soft, consisting almost entirely of the remains of infusoria. The Gulf Stream has literally strewed the bottom of the Atlantic with these microscopic shells; for the Coast Survey has caught up the same infusoria in the Gulf of Mexico and at the bottom of the Gulf Stream off the shores of the
Carolinas that Brooke's apparatus brought up from the bottom of the Atlantic off the Irish coast.
617. Their suggestions.—The unabraded appearance of these shells, and the almost total absence among them of any detritus from the sea or foreign matter, suggest most forcibly the idea of perfect repose at the bottom of the deep sea. Some of the specimens are as pure and as free from the sand of the sea as the freshly fallen snow-flake is from the dust of the earth. Indeed, these soundings suggest the idea that the sea, like the snow-cloud with its flakes in a calm, is always letting fall upon its bed showers of these microscopic shells; and we may readily imagine that the "sunless wrecks," which strew its bottom, are, in the process of ages, hid under this fleecy covering, presenting the rounded appearance which is seen over the body of the traveller who has perished in the snow-storm. The ocean, especially within and near the tropics, swarms with life. The remains of its myriads of moving things are conveyed by currents, and scattered and lodged in the course of time all over its bottom. This process, continued for ages, has covered the depths of the ocean as with a mantle, consisting of organisms as delicate as the macled frost, and as light in the water as is down in the air.
618. The work of re-adaptation, how carried on.—The waters of the Mississippi and the Amazon, together with all the streams and rivers of the world, both great and small, hold in solution large quantities of lime, soda, iron, and other matter. They discharge annually into the sea an amount of this soluble matter, which, if precipitated and collected into one solid mass, would no doubt surprise and astonish even the boldest speculator with its magnitude. This soluble matter cannot be evaporated. Once in the ocean, there it must remain; and as the rivers are continually pouring in fresh supplies of it, the sea, it has been argued, must continue to become more and more salt. Now the rivers convey to the sea this solid matter mixed with fresh water, which, being lighter than that of the ocean, remains for a considerable time at or near the surface. Here the microscopic organisms of the deep-sea lead are continually at work, secreting this same lime and soda, etc., and extracting from the sea water all this solid matter as fast as the rivers bring it down and empty it into the sea. Thus we haul up from the deep sea, specimens of dead animals, and recognize in them the remains of creatures which, though invisible to the naked eye, have nevertheless assigned to them a most important office in the physical economy of the universe, viz., [that of regulating the saltness of the sea (§ 489). This view suggests many contemplations. Among them, one, in which the ocean is presented as a vast chemical bath, in which the solid parts of the earth are washed, filtered, and precipitated again as solid matter, but in a new form, and with fresh properties. Doubtless it is only a readaptation—though it may be in an improved form—of old, and perhaps effete matter, to the uses and well-being of man. These are speculations merely; they may be fancies without foundation, but idle they are not, I am sure; for when we come to consider the agents by which the physical economy of this our earth is regulated, by which this or that result is brought about and accomplished in this beautiful system of terrestrial arrangements, we are utterly amazed at the offices which have been performed, the work which has been done, by the animalculae of the water. But whence come the little silicious and calcareous shells which Brooke's lead has brought up, in proof of its sounding, from the depth of over two miles? Did they live in the surface waters immediately above? or is their habitat in some remote part of the sea, whence, at their death, the currents were sent forth as pall-bearers, with the command to deposit the dead corpses where the plummet found them.
619. Animalculæ at the surface of the sea.—Fellow-labourers as Foster, and Toynbee, and Piazzi Smyth, are beginning to dip into the surface water of the sea for its animalculæ. They are making interesting discoveries, and have gone quite far enough to show that this field is exceedingly rich, and that labourers in it are greatly needed.[4]
- ↑ The greatest depth, from which specimens of bottom have been obtained, is 19,800 feet (3300 fathoms) in the North Pacific.
- ↑ In a paper upon the organic life-forms from unexpected great depths of the Mediterranean, obtained by Captain Spratt from deep-sea soundings between Malta and Crete, in 1857, and read before the Berlin Academy, November 27, 1857, Ehrenberg said, "Especially striking among all the forms of the deep are the Phytolitharia, of which fifty-two in number are found. It would not be strange if these fifty-two forms were spongoliths, since we expect to find sponge in the sea. But a large number, not less than twenty kinds of Phytolitharia, are fresh-water and land forms. Hence the question arises, How came these forms into those depths in the middle of the sea? "Naturally one looks at first to the Nile and the coasts; but the sea current carries the turbid Nile water eastward; for the current, according to Captain Smyth, especially in the middle of the sea, not only in the Levant, but also in the southern edge, is clearly a constant castwardly one. Besides, there are among the forms some northern ones—e. g., Eunotia triodon, Campylodiscus clypeus, and many gallionella. This peculiarity may, perhaps, indicate a lower return current, hitherto observed only at Gibraltar, which probably brings into this basin the forms from the Northern European rocks. Thus, for instance, the Danube may bring the Swiss forms in that circulation. But, on the other hand, a highly striking agreement with the forms of the 'trade-wind dust' is not to be overlooked. "In reference to the question of permanent life in these most recent deep-sea materials, it may be observed, that the forms which we find are astonishingly well preserved, and in very large proportion, sometimes forming the principal mass of the earthy bottom. "The striking fact, moreover, that every one who has the opportunity to compare accurately the microscopic forms of the whole land and sea under great variety of circumstance does, out of even the smallest specimens of the bottom, deduce so much that is new and peculiar to him, is no light testimony to show that the depth is not merely a collection of rubbish of the dead surface-like, however much there must be of fragments which naturally and undoubtedly deposit themselves there. I have considered this final remark necessary, because the distinguished Sea-knower in Washington, often so kindly supplying and instructing me with material, has recently, in a report on Sub-oceanic Geography, New York, January 8, 1857, page 5, and yet more in detail in a late private letter, expressed a view opposite to that here laid down by me, in which however, I cannot coincide, for the reasons given above." As these sheets are passing through the press (Nov. 22, 1860), a copy of Dr. Wallach's " Notes on the Presence of Animal Life in Vast Depths of the Sea," dated "Off Rockall, Nov. 8, 1860," has been placed in my hands. From this interesting monograph it appears that Captain Sir Leopold M'Clintock, during his recent survey, in H. M. steamer the "Bulldog," of the telegraphic route viâ Greenland, brought up living star-fish, adhering to the deep-sea line. "In sounding," says the doctor, p. 22, "not quite midway between Cape Farewell and Rockall, in 126 fathoms, whilst the sounding apparatus brought up an ample specimen of coarse gritty-looking matter, consisting of about 95 per cent, of clean Globigerina-shells, a nmnber of star-fishes, belonging to the genus Ophiocoma, came up, adherent to the lowest 50 fathoms of the deep-sea line employed." These star-fishes were alive. They continued to move about for upwards of a quarter of an hour. The "red and light-pink coloured tints" being as clear and brilliant, says the doctor, as seen in their congeners inhabiting its shallow waters where the sun's rays penetrate freely. One of the animals was dissected, which was found to differ in no respect (p. 23), as regards internal anatomy, from the species inhabiting shallow water. He found in the alimentary cavity numerous Globigerina-shells, more or less completely freed of their soft contents. These contents, and the bringing up of these living specimens, is held by the "biotics" to be proof conclusive as to the existence of animal life in the depths of the sea. So far from settling the question, these star-fishes leave it, I submit, exactly as it was before. They were not brought up by the arming of the lead. They were adhering to the line by their own volition. They might have taken hold of the line near the surface as well as near the bottom. It is difficult, it is true, to account for their being afloat so far out at sea; but how often are frogs and fishes found under circumstances and in conditions which cannot be accounted for! Their coming out of the sea adherent to the line proves nothing. But the creature had Globigerina-shells in its stomach; therefore, say the biotics, these shells must also have lived at the depth of 1260 fathoms. Not so: wherever the star-fish lived, he must have food, and he could collect these mites of things as well near the top as the bottom of the sea. Its anatomical structure, and the brilliancy of its colour—red and pink—seem to prove the anti-biotic view quite as much as the other circumstances of the case prove the biotic. Life in the depths of the sea is an interesting question, and the plan which seems most capable of settling it has been already suggested, wide § 613.
- ↑ "West Point, N, Y, January 29, 1856.
"My dear Sir,—I have examined with much pleasure the highly interesting specimens collected by Lieutenant Brooke, of the United States Navy, which you kindly sent me for microscopic analysis, and I will now briefly report to you the results of general interest which I have obtained, leaving the enumeration of the organic contents and the description of new species for a
more complete account, which I hope soon to publish. The specimens examined by me were as follows, viz.:
"No. 1. Sea bottom, 2700 fathoms; lat. 56° 46′ N., long. 168° 18′ E. ; brought up July 19, 1855, by Lieutenant Brooke, with Brooke's lead.
"No. 2. Sea bottom, 1700 fathoms; lat. 60° 15′ N., long. 170° 53′ E.; brought up as above, July 26, 1855.
"No. 3. Sea bottom, 900 fathoms; temperature (deep sea) 32°, Saxton; lat, 60° 30′ N., long. 175° E.
"A careful study of the above specimens gave the following results:
"1st. All the specimens contain some mineral matter, which diminishes in proportion to the depth, and which consists of minute angular particles of quartz, hornblende, feldspar, and mica.
"2nd. In the deepest soundings (No. 1 and No. 2) there is the least mineral matter, the organic contents, which are the same in all, predominating, while the reverse is true of No. 3.
"3rd. All these specimens are very rich in the silicious shells of the Diatomaceæ, which are in an admirable state of preservation, frequently with the valves united, and even retaining the remains of the soft parts.
"4th. Among the Diatomes the most conspicuous forms are the large and beautiful discs of several species of coscinodiscus. There is also, besides many others, a large number of a new species of rhizosolenia, a new syndendrium, a curious species of cheetoceros, with furcate horns, and a beautiful species of asteromphalus, which I propose to call Asteromphalus Brookei, in honour of Lieutenant Brooke, to whose ingenious device for obtaining deep soundings, and to whose industry and zeal in using it, we are indebted for these and many other treasures of the deep.
"5th. The specimens contain a considerable number of silicious spicules of sponges, and of the beautiful silicious shells of the polycistinese. Among the latter I have noticed Cornutella clathrata of Ehrenberg, a form occurring frequently in the Atlantic soundings. I have also noticed in all these soundings, and shall hereafter describe and figure, several species of eucyrtidium, halicalyptra, a perichlamidium, a stylodictya, and many others.
"6th. I have not been able to detect even a fragment of any of the calcareous shells of the polythalamia. This is remarkable from the striking contrast it presents to the deep soundings of the Atlantic, which are chiefly made up of these calcareous forms. This diflference cannot be due to temperature, as it is well known that polythalamia are abundant in the Arctic Seas.
"7th. These deposits of microscopic organisms, in their richness, extent, and the high latitudes at which they occur, resemble those of the antarctic regions, whose existence has been proved by Ehrenberg, and the occurrence in these northern soundings of species of asteromphalus and chsctoceros is another striking point of resemblance. These genera, however, are not exclusively polar forms, but, as I have recently determined, occur also in the Gulf of Mexico and along the Gulf Stream,"8th. The perfect condition of the organism in these soundings, and the fact that some of them retain their soft portions, indicate that they were very recently in a living condition, but it does not follow that they were living when collected at such immense depths. As among them are forms which are known to live along the shores as parasites upon the algae, etc., it is certain that a portion, at least, have been carried by oceanic currents, by drift ice, by animals which have fed upon them, or by other agents, to their present position. It is hence probable that all were removed from shallower waters, in which they once lived. These forms are so minute, and would float so far when buoyed up by these gases evolved during decomposition, that there would be nothing surprising in finding them in any part of the ocean, even if they were not transported, as it is certain they often are, by the agents above referred to.
"9th. In conclusion, it is to be hoped that the example set by Lieutenant Brooke will be followed by others, and that, in all attempts to make deep soundings, the effort to bring up a portion of the bottom will be made. The soundings from any part of the ocean are sure to yield something of interest to microscopic analysis, and it is as yet impossible to tell what important results may yet flow from their study.
"The above is only a preliminary notice' of the soundings referred to. I shall proceed without delay to describe and figure the highly interesting and novel forms which I have detected, and I hope soon to have them ready for publication.
"Yours, very respectfully,"J. W. Bailey.""Lieutenant M. F. Maury, National Observatory, Washington City, D. C."
- ↑ See paper "On the Minute Inhabitants of the Surface of the Ocean," by Captain Henry Toynbee, F.R.A.S. [Naut. Magazine, 1860,]