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of the river, as she caught sight of a face above name of “the Science of the Atmosphere and the the wave—a black and fiendish face, that gazed Ocean." one instant lovingly into her heavenly eyes, and we are just beginning to learn some of the then swept madly, in the whirling, eddying cur- manifold relations which the ocean and the atmorent, down to woe unutterable.
sphere sustain in the general economy of nature. The next morning after Stephen Forster's The sea which covers three-fourths of the surface death, a nol. pros. was entered in the murder of the globe is something more than the highway case, and it may please some to know that Mary for the commerce of nations. It is the fountain Wilson was in court to hear the announcement. from which rise all the streams that make green And for years after that, an old grayheaded man, the earth, as well as the reservoir into which unrecognized by any villager, might be seen al- they all flow. It is an apparatus by which the most any evening standing by the grave of the torrid heat is conveyed to temper the polar cold, murdered wife, and at length some one learned and the polar cold is brought in turn to mitigate that his name was Norton. But the story of the tropical heat. Ellen Dusenberry's early love had been forgotten the atmosphere also, apart from its obvious for twenty years-save by the true heart of her function of vitalizing the blood which courses old lover.
through the veins of every breathing thing, per
forms other duties than that of filling the sails of THE OCEAN AND THE ATMOSPHERE. commerce. It is the great receptacle into which TIEUTENANT MAURY'S “Sailing Direc- all organized matter is cast and from which it is U tions"--a huge quarto volume of well-nigh a again evoked. The carbonic acid which our thousand pages-lies before us. It is designed breathing pours into the air, is taken up by the to accompany and explain the “Wind and Cur-vegetation on the other side of the globe. The rent" and "Whaling" Charts that have won for oxygen which we inhale was perhaps given their author so honorable a place in the scientific out by the cedars of Lebanon. The carbon exworld. At first sight the book would seem to haled by the denizens of London is transmuted concern those only who do business upon the into the flowers that adorn our western prairies. great deep. A landsman, upon casual inspection, Every blade of grass on the pampas of South would perceive little to interest him in the long America, every leaf in the jungles of the Himacolumns bristling with the names of vessels, layas, is distilling oxygen for the Esquimaux and figures, dates, abbreviations, and symbols, as un- the Laplander The atmosphere is also a great intelligible to him as the inscriptions dug up at hydraulic engine that pumps up from the ocean Nineveh. Then he would encounter page after every drop of water that descends in dew or falls page of matter like this:
in showers. It conveys it for leagues, and “ Barque Parthian (Smith). May, 13, 1853. thousands of leagues, and deposits it upon the Lat. 50° 55' S.; long. 63° 52' W. Barom. 29.1; mountain sides or on the thirsty plain. The temp. of air, 50°; of water, 48°. Winds: N., water that swells the Mississippi or thunders over N.W., S.S.W. Fine weather; whole sail breeze." | Niagara was caught up from the Indian Ocean
And so on for a score or two of pages in suc- or the Pacific. The dew drop that glistens on cession. Here are facts enough to satisfy Mr. the flower at our door, once sparkled in the surf Gradgrind himself. The reader's first feeling is that breaks upon the coral reefs of the South one of pity for the printer who, day by day and Seas. The water that flows in the visible chanall day long, has been picking up, letter by letter nels of the Amazon, the Volga, and the Nile, has and point by point, these wearisome paragraphs; before flowed in the invisible channels of the atand commiseration for the proof-reader who has mosphere. Those unseen rivers flowing through strained eye and brain to make sure that every the air are as constant in their courses as those letter and point and symbol is in its proper that run in visible channels through the land. place.
The atmosphere draws up from the oceans of the A very dry book, apparently, is this volume of Southern Hemisphere an amount of water suf "Sailing Directions." It reminds one of the ficient to drain them to their lowest beds withtoppling piles of brick and stone, wide beds of in a period of time less than that embraced in mortar, and heaps of planks and scaffolding that recorded history. The larger portion of this block up our thoroughfares. Yet, under the is borne aloft, and poured into the seas of the guidance of the architect, these unformed heaps Northern Hemisphere; yet the one is never empty, and shapeless piles assume form and proportions ; | the other never overflows the bounds set to it of growing up into the airy spire of a Trinity Church | old. or the graceful facade of a Saint Nicholas Hotel. Thus ocean and air are ever working together In like manner from this seeming chaos of col- for the well-being of the dwellers upon dry land; umns and paragraphs is evolving-we may even and were any great change to be wrought in the say has already evolved-one of the most beauti- properties or relations of either, an entire alteraful sciences that has ever tasked and rewarded tion would take place in the whole economy of the exertions of the human intellect.
our planet. Science that has hitherto busied itself For this science Humboldt has proposed the almost exclusively with the dry land, is now ex name of " The Physical Geography of the Sea." tending its researches into the regions of the air To us this seems an inadequate designation. We and the water, and from them gathering the would propose for it the more comprehensive richest harvests. The foremost explorer and pioneer in this new field is undoubtedly Lieute- It is the purpose of Lieutenant Maury to collect nant Maury, and the main results of his labors at least a hundred observations for each month are embodied in these charts and in the volume upon every one of these districts of five degrees; which accompanies them
this alone would make a total of more than a Nothing can be more simple and effective than million and a half of observations. For the disthe manner in which were collected the facts upon tricts which lie along the great routes of comwhich his theories and speculations are based. merce, this number has already been far exceeded. As many log-books and journals of voyages as Copies of these charts, as rapidly as they were possible were collated, and from the notices con- completed, bave been placed in the hands of tained in them were laid down the various tracks every master of a vessel who would engage to which had been pursued, together with all the make the observations required, and at the end information they contained as to winds and cur- of each voyage transmit them to our National rents and other nautical phenomena. But the Observatory. Thus the observations made by results obtained from these immethodical observa- each, enure to the benefit of all. Every master tions, though valuable in themselves, only served of a vessel, no matter in what part of the ocean to show what might be accomplished were a he may be, has the benefit of the experience of series of combined efforts made with a definite hundreds who have been there before him. He end, and upon a scale sufficiently extensive. can tell precisely what winds their united expeMariners sailing upon every sea were speedily rience gives him reason to expect, at any season enlisted to keep an accurate record of all the of the year; in what quarters he may hope for facts relating to winds and currents, storms and favorable ones, and where he has to apprehend calms, and the like, at stated hours during every those that are adverse. He multiplies his own day of their voyage. These were to be trans experience by that of the thousand others who mitted to Lieutenant Maury, to be collated and have undertaken the like voyages. arranged, so that the information collected by For the great commercial routes, the informaeach might be rendered available for the benefit tion thus collected has been still further generalof all.
ized. Precise tracks have been laid down, by adIt was not long before reports began to pour hering to which the greater number of favorable in from every sea whitened by American sails. circumstances may be secured, and the greater They came from among the Arctic icebergs and number of adverse ones avoided. And it has the palm-shaded islands of the Pacific ; from the come to be generally admitted that just in the great ocean highways furrowed by the commerce degree in which the track laid down upon the between the Old World and the New, between charts is adhered to, in just so far a speedy vorthe East and the West, and from those recently age may be anticipated. Previous to the publiopened up to the golden regions of California cation of these charts the average length of the and Australia-highways almost as well defined voyage between our Eastern ports and California as are the roads cast up upon the land ; from the was one hundred and eighty-three days. The two stormy capes which form the southern ex- average length of the voyages between the same tremities of the eastern and western continents ; 1 ports, performed by vessels on board which these from the far off, wide-lying seas in which our charts are used, has been one hundred and thirtyadventurous whalemen chase leviathan, hugest six days; and in instances not very rare, it has of things that swim the ocean flood.” A thou- been performed within less than a hundred-in sand navigators were soon enlisted in the enter- one case in eighty-eight days. In the most sucprise. The abstracts of these reports, preserved | cessful of these voyages—those which have been at the National Observatory, already fill nearly performed in less than half the time formerly four hundred large manuscript volumes, contain-consumed the track of the vessel's keel through ing records made upon nearly two millions of the ocean corresponds almost precisely with that days-as many as have elapsed since man was traced for its guidance upon the chart. first placed upon this planet. These constitute The Whaling Charts have been constructed the raw material, the brick and mortar, from upon the same general principle, with such modiwhich is constructing and to be constructed, the fications in the details as the nature of the subScience of the Ocean and Atmosphere.
|ject demands. It has long been known that From the materials thus brought together were whales migrate from season to season, following constructed the Wind and Current Charts. Upon their food through the ocean. The object of the the “ Pilot Charts” the entire surface of the ocean charts is to show at a glance in what portion of was marked off into squares of five degrees of the ocean the whales may be expected to be found latitude and longitude. In each of these divisions at each season. The whole ocean is in these was entered the results of all the observations charts also divided into squares of five degrees, made by all the navigators who had sailed over it in which, by a simple arrangement of lines, is inin each month. The number of observations was dicated how many days during each month all given; the number of days in which the wind the vessels who send in their reports have been had blown from each point of the compass; the on the lookout for whales in each division, and temperature of the air and water, the number of upon how many days whales have been seen, days of storm and calm, and fair weather; the distinguishing moreover between the “right" and force and direction of the currents; and every the "sperm" whales. The experience of any one thing which could be of service to the sailor. whaler can hardly extend to beyond a dozen or a score of voyages at most; but by the aid of cific. The main body, however, turns due north, these charts each may have the full benefit of the skirting the shores of Chili and Peru, whence it knowledge gleaned by a half thousand others. turns again westward into the bosom of the Pa
The grand series of investigations thus set on cific, cooling the ocean that encircles the island foot in this country in due course of time at- groups of the South Seas, and passing onward tracted attention abroad. Our own government through the Pacific into the Indian Ocean. In early entered into the seheme, by ordering all our the north, it is broken against the Chinese coast, naval commanders to make the required obser Australia, and the islands of the Indian Archivations, and by giving it every furtherance re pelago, through which a large portion makes its quired. Proposals for like co-operation were way into the Indian Ocean. Passing down the made by the maritime nations of Europe, and in eastern shore of Africa, it doubles the stormy August and September, 1853, a conference was Cape, misnamed of Good Hope, skirts the coasts held at Brussels for the purpose of devising and of Guinea, and the dolorous region cursed by the perfecting a uniform plan of operations. The slave-trade, abhorred by God and man, and engovernments of Great Britain, France, Russia, ters the great caldron of the Bight of Benin, into the Northern Powers, and all the maritime na- which, on the very line of the equator, pours the tions of Europe were represented by competent current of the mysterious Niger. delegates. Our own government was represented Here the waters, raised to a high temperature by Lieutenant Maury. A plan of mutual assist- by the fierce rays of a vertical sun, take their ance was adopted ;, and the conduct of the oper-way westward, across the Atlantic, forming the ations was placed under the solemn sanction of Equatorial Current of the Atlantic Ocean. The public law. No war that might arise was to in- coast of Brazil protrudes into the Atlantic like a terrupt them. A Russian vessel enlisted in the wedge, having Cape Saint Roque as its apex. work may be taken and become a prize to its Upon this wedge the current splits, one portion captors; but the observations made in pursu- turning to the south, giving the coast of Patagonia ance of this plan are sacred, and are to be trans- and the Falkland Islands a European climate. mitted unharmed to our National Observatory. The other portion goes to the north, a part difThus, whether in war or peace, new acquisitions fusing itself over the Atlantic, toward the south will continually be made, new conquests won; of Europe, while the remainder, following the conquests defiled by no blood, stained by no rap line of the coast, passes through the Caribbean ine; won by no nation at the expense of an- Sea, and enters the Gulf of Mexico; whence it other: conquests won from the elements of na emerges with augmented volume as the Gulf ture for the well-being of all men forever.. Stream. In thus tracing this great current, its
Valuable as are the results of this grand series general direction only has been given. In all of observations in a commercial and pecuniary parts of its course it meets counter currents, point of view, their scientific aspects are of still which sometimes deflect it from its course ; and higher and more general interest. New light sometimes it dives under, so that the surface curhas been shed upon some of the most mysterious rent tends in precisely the opposite direction from problems in the economy of nature; such, for the one indicated. example, as the great atmospheric and oceanic The Gulf Stream is more accurately known currents, by means of which a perpetual inter-than any other of the ocean currents. It emerges change is kept up between the temperature of from the Gulf of Mexico as a well defined river the tropical and polar regions. It is not too much of warm water, inclosed between banks of cold to hope that, when the whole area of the ocean water. For hundreds of miles the line between has been covered over with a net-work of observa the blue waters of the Stream, and the greenish tions, materials will be accumulated, from which waters of the surrounding ocean, is as visible to may be framed a complete and satisfactory theory the eye as the line between a river and its banks. to explain the currents in the ocean, that hitherto So sharp is the line of separation that a vessel unrevealed mystery of the watery world. is not unfrequently beheld with one part mani
Enough has already been accumulated to show festly in the blue water, and the other part in the that there is a constant current of cold water set- green. Long after the difference in color has ting from the poles of the earth toward the equa- become imperceptible, the thermometer tells with tor, and consequently a counter current of heated unerring certainty when a vessel has passed from water from the equator to the poles. Each of the cold waters of the Atlantic into the warm these counter currents is in turn a surface and an current of the Stream. under current.
As it emerges through the Straits of Bimini, As a starting point in the investigation, may it is thirty-two miles wide, probably twelve or be taken the great Equatorial Current which we fifteen hundred feet deep, and flows at the rate find flowing from the vast expanse of water around of four or five miles an hour. Careful calculathe Antarctic pole. It pours a constant flood of tions show that it conveys from the Gulf of Mexcold water northeastward toward the western ico an amount of water three thousand times shores of South America. Encountering the greater than that brought into it by the Missiscoast of America, it is divided and turned from sippi ; and that it carries away to the north a its course, one portion rounding Cape Horn, often supply of heat sufficient to keep in a fluid state baffling for days and weeks those navigators who a river of molten iron as large as our great “Faendeavor to pass from the Atlantic into the Pa- ther of Waters." It follows the line of the coast, at a considerable distance, until it reaches Cape | winds, and found their way out by the only pracHatteras, by which time it has spread to a width ticable channel. The Gulf Stream was declared of about one hundred and seventy-five miles. to be like a river on the land descending from a From this point it rapidly diffuses itself, less higher to a lower level, and thus gaining the imhowever by actually mixing its waters with those petus by which it forces its way down to the of the surrounding ocean, than by flowing over north. But it was soon found that no such differthem, as a body of oil would flow over the sur ence of level existed; or rather that the bed of face of a lake. Its course now veers almost the Stream, instead of descending to the north, directly east, standing straight across the Atlan- actually ascended at a rate of inclination greater tic, covering the surface of the ocean with a warm than the average descent of the Amazon or the mantle which protects the coasts of Europe from Ganges. the extremes of temperature due to their northern Still further observations showed that while the latitude. When the stream reaches the neigh-Gulf Stream was pouring a current of warm water borhood of the British islands, it is divided, one to the north, a counter current of cold water was portion tending toward the polar regions, giving at the same moment running beneath and beside to Spitzbergen, in latitude 80°, a mean tempera- it directly into the Gulf. Both streams, thus ture as high as that of the shores of the central flowing in contrary directions, could not be runpart of Hudson's Bay; to Iceland it gives a cli- ning down hill. Vessels drifting northward near mate as warm as that of Newfoundland. It the Great Banks of Newfoundland not unfrequentenables the Lapland peasant to cultivate his bar- ly encounter huge icebergs making their way to ley in a latitude which upon the Western Con- the south directly in the teeth of both wind and tinent is doomed to perpetual sterility. The green the surface current of the Gulf Stream. They shores of Ireland are on the same parallel with sometimes rise hundreds of feet above the water; the ice-bound coast of Labrador; Paris lies to and philosophy has demonstrated that for every the north of Quebec; the crowded port of Liv hundred feet they rise above the surface, they erpool is as far north as those bleak countries must sink a thousand feet below. They therewhere the Esquirnaux build their snow houses, fore penetrate through the superficial current and patiently watch the rising of the seals from flowing northward, down into a submerged souththeir breathing holes in the ice.
ern current, far enough for its force to prevail All this difference between the climate of the over the one which was tending to bear them two hemispheres a difference in favor of the northward. Ships, drawing but a few feet of Eastern Continent fully equal to that produced water, never sink into this under current, and so by twenty degrees of latitude, is the gift of the partake only of that which flows upon the surface. northern branch of the Gulf Stream; while the More minute observations showed that this other branch is equally bountiful to the countries ice-bearing current from the Arctic regions enof Southern Europe. To France and Spain it countered the head of the Gulf Stream near the gives the vine and the olive. Thus long before the Banks of Newfoundland, and that it was there bold Genoese turned his prow toward the West- split into two portions, the one running inshore ern World, that Western World had been be-between the American coast and the Gulf Stream; stowing upon the natives of Europe the blessings while the other plunged under and flowed beneath of a mild and equable climate.
the warm surface current into that very Gulf of But whence comes this immense body of water Mexico, from out of which the other current was thus perpetually forced out of the Gulf of Mex-pouring. ico? "Where are the hidden fountains of this Here then was a solution of one portion of the great ocean stream, by the side of which the problem of the Gulf Stream. The waters which mightiest rivers of the land are but tiny brooks ? ) pour forth to the north, heated from the great What force impels its warm currents straight caldron of the Gulf, flow into it, as an under cus through the surrounding waters, and spreads rent, from the northern regions. But the other them abroad over the surface of the ocean? The branch of the problem seemed by this very soluwater borne in this Stream from the Gulf of tion to be involved in still deeper mystery. What Mexico must somehow find its way back; for was the impelling force that set in motion these that great basin shows no signs of being emptied; two opposite currents, thus flowing side by side, while the northern seas into which it pours its and over and under each other? mighty current never overflow.
For the solution of this problem Lieutenant The Gulf Stream was once looked upon as a Maury has furnished some suggestions in which simple prolongation of the Mississippi. This we are confident will be found the germs of the supposition was conclusively set aside by the true theory by which will be explained not only demonstration that it would require three thou- the Gulf Stream, but all of the other currents of sand rivers like the Father of Waters to bring the ocean. into the Gulf the amount of water borne out of Let us, in order to elucidate this theory, supit by the Gulf Stream; even laying quite out of pose that by some process all the water of one account the immense evaporation continually portion of the sea—the Gulf of Mexico, for ex taking place from such a mass of water lying ample-were suddenly to become of less specifie under so warm a sun.
gravity than the other: or we will say, converted It was then suggested that the waters of the into oil. What would be the consequence? Why, ocean were driven into the Gulf by the trade the surrounding waters would press upon the lighter fluid, and force it out in any direction in solution; so that the remaining water is salter, where there was no obstacle; spreading it abroad and therefore heavier than it was before. This over the surface, while the heavier fluid would change takes place only on the surface; and the pour in as an under current to supply the place thin layer of water thus rendered heavier sinks of that forced out, keeping the whole surface at by its weight, while a portion of fresher and a uniform level. Now let us further suppose that lighter water rises to the surface to take its place. the oil as it approached the pole was changed to A continual current up and down is thus prowater again, while that which flowed into the dụced in the waters between the tropics. In the Gulf was constantly changed into oil, and so on mean while, in the regions to the north-at the in continual succession; we should then have poles especially-more water is deposited from just the phenomenon of the Gulf Stream: an the atmosphere than is taken up by evaporation. upper current of light fluid continually pouring This water is all fresh, and consequently it tends out from the Gulf, and an under current of heavier to make the polar waters lighter than they otherfluid just as constantly pouring in. ,
wise would be. So that, owing to saltness, Our supposition corresponds to the fact in all evaporation, and precipitation, we have a great essential particulars. Water, within certain limits, change continually wrought in the specific gravity expands by heat, therefore becoming lighter; and of the water of the ocean. And as was shown, contracts by cold, so becoming heavier. The whenever such a chango is wrought, two counter operation of heat alone would simply cause a currents are of necessity set in motion, the one general current of warm water to flow on the at the surface and the other in an opposite direcsurface from all equatorial regions toward the tion below the surface. poles, to be replaced by as constant and uniform The saltness of the ocean, it may therefore he an under current from the poles to the equator. fairly presumed, contributes in no small degree
This is precisely what takes place in respect toward causing the ceaseless currents by which to the other great fluid body, the atmosphere. the waters of every sea are mixed and mingled Along the line of the equator, extending for some together. The course of investigation now in degrees on each side, is a belt of atmosphere in progress renders it probable that the currents of which there are no constant winds. Here the the ocean are primarily owing to these changes air heated by the vertical rays of the sun becomes continually going on in the specific gravity of the rarified and rises. From each side of this equa- waters of different portions. torial belt the air of a lower temperature rushes Thus the currents of the atmosphere and of in to supply the partial vacuum; thus forming the ocean are brought under one law. They the trade winds, which blow steadily from the both are traced back to the power of gravitation. direction of the northern and southern poles. The same law that keeps the planets in their These great atmospheric currents are as steady orbits, and preserves the stars in their places, is and uniform in their course as is the current of shown to be identical with that which impels a great river seeking its way to the sea. The each particle of air and water in its ceaseless storms and hurricanes, the typhoons and whirl- | course around the globe. winds, which lash the surface of the ocean into There is still another interesting subject of waves, and strew its bottom with the wrecks of speculation connected with the saltness of the navies, bear no greater proportion to the steady ocean. We know that every river which flows and equable flow of the trade winds, than the through the land sweeps along with it to the sea eddies and whirls in the Mississippi do to the a quantity of solid matter held in solution. This general direction of its current.
consists mainly of common salt, sulphate and Now were the rays of a vertical sun the only carbonate of lime, soda, and similar substances. force that disturbs the equilibrium of the ocean, All this goes into the sea; but not a particle ever and were the free movements of the waters un- finds its way back to dry land again. The water obstructed by the conformation of the bottom and taken up by evaporation is pure and fresh. It shores of the ocean, we should have oceanic cur- is borne in viewless channels through the atmosrents answering precisely to the trade winds : phere; is condensed, and falls to the earth as that is, a constant surface flow of heated water rain, or dew, or snow. It penetrates the strata from the equator to the poles, with as constant of rocks charged with saline matter, which it disan under current of cooler water from the poles solves and bears on with it to the sea again. Hero to the equator.
it circulates through the ocean from the poles to But there is another disturbing force which the tropics, from the surface to the lowest depths, comes in to modify, and in some instances greatly and from the bottom to the surface, until it is to augment this of which we have been speaking. taken up again, and goes through the same great
The water of the ocean contains in solution a round. It is more than probable that every drop large amount of saline and other matter, which, of water in the ocean has traveled these rounds as is well known, render it considerably heavier many times since our present order of things was than an equal volume of fresh water. From established. certain portions of the ocean-those especially Yet though from age to age so vast an amount over which the trade winds blow-a much larger of saline matter has been continually poured into quantity of water is taken up by evaporation than the ocean, the composition of its waters has reis returned in the shape of rain, But fresh water mained unchanged. The ocean is no more briny only is taken up, leaving behind all the salts held than it was five thousand years ago. What be