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pipe. “From the banks of Newfoundland | but the meduse, or sea-nettles, its princito the shores of Europe is the basement pal food, are bred in the warm seas of —the hot-air chamber in which this pipe the south. From the Gulf of Mexico, is flared out, so as to present a large cool the great nursery of these medusæ, the ing surface. Here the circulation of the Gulf Stream carries them in shoals for atmosphere is arranged by nature; and it thousands of miles, to feed the starving

; is such, that the warmth thus conveyed whale in its own gelid waters.* into this warm air-chamber of mid-ocean One of the most remarkable properties is taken up by the genial west winds, and of the Gulf Stream, is the influence which dispersed, in the most benign manner, it exercises over the meteorology of the throughout Great Britain and the west ocean. The most furious gales sweep of Europe." In support of these views, along with it; and it is doubtless the our author informs us, that the maximum cause of the fogs of Newfoundland, which temperature of the Gulf Stream is 86°, or are so dangerous to navigation in winter. about go above the ocean temperature ; Many gales have been traced to the Gulf that it loses 2° by an increase of 10° of Stream from their origin; and gales which latitude; and that, after running 3000 rise on the coast of Africa, as far south as miles northward, it still preserves, in win- 10° or 150 of N. latitude, have been ter, the heat of summer, and in this state known to join it, and to travel with it, crosses 40° of north latitude. Here it turning around to recross the Atlantic for overflows its liquid banks, and spreads it- the shores of Europe. Gales thus atself for thousands of square leagues, over tracted to the Gulf Stream are the most the cold waters around_-“covering the terrific on the ocean, and their course ocean with a mantle of warmth,” and is marked by the most serious disasters. carrying with it a mild and moist atmo- In 1854 upwards of seventy vessels were sphere, which mitigates in Europe the wrecked, dismasted, or damaged, in one rigors of winter, and extends its genial of these tornadoes; the current of the influence even into the polar basin of stream running in one direction, and the Spitzbergen. Ireland, says Lieutenant wind blowing in another, so as to create Maury, is thus made the “ Emerald Isle a sea of the most frightful kind. These of the Sea,” and the shores of Britain storms are said to be, for the most part, clothed with evergreen robes, while, in rotatory ones, such as have been described the same latitude, Labrador is fast bound by Piddington, Redfield, and Reid; but in ice.

it is a question still to be settled, why But while the Gulf Stream is thus gene- these storms are attracted towards the rous to the north of Europe, its beneficial Gulf Stream, and follow it in its course. influences are felt in the south. The cold We have thus seen, under the guidance waters from the north descend towards of our distinguished author, how the the Equator, and moderate the burning equatorial winds convey the heat over the climates in the Caribbean Sea, and round waters of the tropics in the Northern the Gulf of Mexico. These cold currents Hemisphere, raising the temperature of bring along with them the fish of the the Atlantic, warming even the Arctic northern seas, and thus give the inhabit- Seas, and therefore necessarily improving, ants of the south a supply of fish far su- to some extent, the climate of the west perior to that which is bred in their of Europe. We can not, however, agree heated waters. The fish of warm climates, with Lieutenant Maury in regarding the though beautiful and gorgeous in their Gulf Stream as the sole, or even the princolors, are soft and unfit for table; while cipal, cause of the temperature which in the current of cold water in the Pacific, characterizes the warm meridian that called Humboldts Current, which sweeps passes through the west of Europe. In the shores of Chili, Peru, and Columbia, a former article, relative to the distribuand reaches even the Gallipagos Islands,

* Of the coast of Florida, shoals of young meduunder the Line, there is throughout the

sæ have been seen, thickly covering the sea for whole of that distance an abundant supply many leagues. A sea captain, bound to England, of excellent fish. These cold and warm was five or six days in sailing through them. On currents, therefore, are the great high- his return, sixty days afterwards, he encountered the ways through which fishes travel from

same shoal, and was three or four days in passing

through it. one region to another. The whale, it is

+ See Review of Humboldt's "Central Asia," in well known, can not exist in warın waters; I vol. v., pp. 491–503.

tion of heat over the globe, we have and the spider's line glitters with the vashown that there are in the Northern ried tints of the sun. The silence of Hemisphere two poles of maximum cold death is broken only by the hum of life.

-one in Canada, and another in Siberia ; Over this trance of nature a change speedtwo meridians of maximum cold, passing ily supervenes. The distant forest annearly through the cold poles; and two nounces the approach of the tempestof maximum heat, nearly at right angles the oak and the pine are crushed by its pow. to them. We have shown, also, that the er; the proudest monuments of human two magnetic poles are nearly coïncident skill are leveled with the dust; and the with the poles of maximum cold; and we slumbering ocean, chafed into fury, dashes are therefore led to regard the earth as a the war-ship against its cliffs, or sinks it great thermo-magnetic apparatus, in which beneath its waves. Resting upon the the distribution of its temperature is re- stream, and lake, and sea, the porous gulated by internal or external causes, air sucks up their waters in vapor, forms depending upon magnetic, galvanic, or with it the fleecy or the watery cloud, and chemical agencies. The difference be- retains its precious charge till its service tween the temperatures in the same lati- is demanded in rain or in dew, in bail or tudes (130 in the lat. of 50°, and 17° in in snow. As the pabulum of life, the air the lat. of 60°) on the cold and warm me- of the atmosphere exercises still higher ridians, is too great to be produced by functions. It is the food of whatever any genial currents in the ocean ; and we breathes, the fuel of whatever burns, the can hardly conceive how even a much essence of whatever grows, the spirit of higher temperature than that of the Gulf whatever dies--the soul, in short, of matStream could, after its enormous diminu- ter--its element when it exists, its residution by the eastern expansion of the cur- um when it decays. It is only, however, rent, affect even the Northern Ocean to in its relation to the geography of the any marked extent. That it should affect sea, that we can treat of the functions of the inland climates of the West of Europe, the atmosphere. appears to us still more problematical. Between the parallels of latitude 30° The variation of temperature in the warm N. and 30° S. of the equator, winds called European meridian, as the cosine of the the Trade - Winds, blow almost unceaslatitude, indicates a cause of a more gene- ingly. Those on the north of the equator ral nature than the intrusion of an oceanic blow from the north-east to the southcurrent; and when we consider that this west ; and those to the south of the equalaw is indicated also by the temperature tor from the south-east to the north-west. of the earth--of springs deeply seated, In their motions, the trade-winds are and beyond the influence of superficial as steady and constant as the current of a agencies—we feel that we are not pre great river, always moving in the same sumptuous in questioning the opinion, that direction, unless when they are occasion. the Gulf Stream, though it may influence, ally turned aside by a desert to blow in does not regulate the climate of the Monsoons, or as land and sea-breezes. The Northern Hemisphere.

northern edge of the north-east tradeWith the physical geography of the sea, winds is variable. In spring they are so the atmosphere of the earth has a neces- near the equator, that they sometimes sary and an interesting connection. What reach only to the parallel of 15o. As the moon is to the tides, the atmosphere those two master currents of air are conis to the ocean. We must study the tinually blowing from the poles to the character and condition of the one, in or- equator, it necessarily follows that the air der to understand the motions and laws thus taken from the poles must be reof the other. The air which surrounds placed by other air from the equator. the earth extends at least to the distance This return current must, therefore, blow of fifty miles, growing thinner and thinner in the upper regions of the atmosphere, as it recedes. At the top of the highest and opposite to the wind which it remountains, it is scarcely sufficient to sus places. Had the earth been at rest, these tain life and to propagate sound. Though winds—the trade and their return curit presses upon every square inch of our rents—would have moved from north to bodies, we do not feel its influence. When south, and from south to north; but in conat rest, we are sensible only to its heat or sequence of the rotation of the earth from its cold. The aspen leaf rests on its stalk, I west to east, both the direct and counter currents move in a direction intermediate of the autumn, winter, and early spring between the two motions to which they of the North, the sun is throwing an inare subject-namely, in south-easterly and tense heat upon the seas of the Southern south-westerly, and in north-easterly and Hemisphere, and therefore raising a mass north-westerly directions. When the of vapor into the upper regions of the atnorth-east trade-winds meet the south- mosphere, from which it is carried in an east ones at the equator, they produce a upper current by the south-east tradecalm, thus forming the belt of Equatorial winds, and set free by condensation in calms. In like manner, when the direct our northern winter. When this upper and return currents from the poles reach current reaches the calms of Cancer, the parallel of 30°, they produce a belt it becomes the surface wind from the of calms, which in the Northern Hemi-southward and westward, and, cooling as sphere are called the calms of Cancer; it goes north, the process of its condensaand in the Southern the calms of Capri- tion begins. Hence our author concludes corn. The breadth of the calms of Can- that our rivers are supplied with their cer, and also their limits, is variable. Ac-waters principally from the trade-wind cording to the season of the year, they regions, and that this is the reason why oscillate between the parallels of 17o and the sea water in those regions contains 38° north.

more salt than elsewhere.* Among the meteorological agencies of The rivers of the Southern Hemisphere, the atmosphere, its two greatest functions, for similar reasons, are supplied with their according to Lieutenant Maury, are to waters by the north-east trade-winds; distribute moisture over the surface of but as the evaporating surface—that is, the earth, and to temper the climate of the area of sea over which they blowdifferent latitudes. Having traveled ob- contains, between the parallels of 70 and liquely over a large space of the ocean, 29° north, only 25,000,000 of square miles, the north-east and south-east trade-winds while the evaporatingsurface in the are heavily laden with moisture when Southern Hemisphere is 75,000,000, the they meet in the belt of equatorial calms. quantity of rain which falls in the latter is The two currents being thus brought into comparatively small. The mean annual collision, the air rises upwards, and expand- fall of rain, which is evaporated principally ing and cooling as it ascends, a portion from the seas of the Torrid Zone, is estiof its vapor, thus condensed, descends in mated at about five feet. If we suppose rains, which are sometimes so heavy and it all to come from that zone, it would be so constant, that, to use the language of equivalent to the waters of a lake 24,000 old sailors, they have scooped up fresh miles long, 3000 miles broad, and 16 feet water from the surface of the sea." The deep! and this water is annually raised up waters thus taken up in vapor and pre- into the sky, and brought down again by cipitated during the collision of aërial currents, and the cold which accompanies * Lieutenant Maury has employed these views in them, supplies the great rivers of the determining the regions where no rain falls, those world, which conduct them to the sea, to where it should be a maximum, and those where be again raised by the winds and breezes less regions are on the coast of Peru, and about the

the climate should be the most equable. The rainwhich blow upon its surface. As the Red Sea, and the Western Coasts of Mexico; and great mass of the ocean lies in the South- the Deserts of Africa, Asia, North America, and Ausern Hemisphere, it is a curious fact that the tralia, are almost rainless. The regions of greatest greatest quantity of rains, indicated by its rains are the abrupt slopes of those mountains which rivers, falls in the Northern Hemisphere. the trade winds

first strike after having blown over In the Northern temperate zone, the annual gonia and to the north of Oregon. The regions of fall of rain is “half as much again " as equable climates are under the Equatorial calms, that in the South temperate zone ;* and where the N. E. and S. E. trade-winds meet fresh it is well known that the great water from the ocean, and keep the temperature uniform courses of the globe, and half the fresh also explains why there is more rain on one side of a

under a canopy of perpetual clouds." Our author water, is in the Northern Hemisphere. mountain than on the other. The Andes, for exam

In explaining this remarkable fact, Lieu- ample, and other mountains which lie athwart the tenant Maury states that, in the late part course of the winds, have a dry and a rainy side, the the exquisite though complex machinery of sumption, anticipate an hour of sunshine the atmosphere, “which never wears out or a day of rain. nor breaks down, nor fails to do its work In his fourth chapter, Lieut.Maury treats at the right time and in the right way.” of land and sea-breezes, those alternate

prevailing winds determining which is the rainy and * According to Johnston's Physical Atlas, the an. which is the dry side—the weather side, or that on nual average in the North is 36 inches, and only 26 which the wind blows, being the wet, and the lee in the South temperate zone.

side the dry one.

In contemplating these wonderful ar- winds which proceed from the sea by day, rangements, we see why the earth is and from the land by night. These breezes round—why its mass and force of gravi- have their origin in the

heating of the land ty is neither greater nor less than it is by day, and its cooling by the radiation of why the proportion between the land its required heat during the night, though and water is as we find it—why the exist- they are occasionally affected by other ing capacity of the atmosphere for moist- causes. Lieut. Jansen,* of the Dutch ure has been adopted — and why the Navy, whose observations, couched in mountain ranges have their present height, language too poetical for science, constiand breadth, and form, and position. To tute the principal part of the chapter, is understand these arrangements, or if be- of opinion that electricity, rain, and other yond our capacity, to be convinced of their causes, have an influence on the regularity existence, is a privilege of no ordinary of the land breezes; and he goes so far kind. If there is any part of the economy as to conjecture, from very insufficient of the material world which seems to be data, that the moon is also an agent, there inexplicable and without law, it is the being, as he avers, in several localities weather with its capricious changes and little land-breeze at full moon, and little its ever-varying and mysterious phenom- sea breeze at new moon. ena. Delayed with calms, or bafled with Among the means of investigating the contrary winds—tossed upon a tempestu- phenomena of the trade-winds, our readers ous sea, or dashed upon the cliffs of the will hardly believe that the microscope ocean-deluged with a water-spout, or has been highly instrumental. In several upset by an iceberg-lost in a fog, or localities, showers of dust of a brick-red struck by the lightning, the sea-faring man or cinnamon color are precipitated in such can hardly believe that he is suffering quantities, as to cover the sails and rigunder a system of beneficial adaptations gings of vessels hundreds of miles from necessary for his happiness and even his land. These showers produce what the existence. Nor is the landsman less seamen calls“ red-fogs,” or “sirocco," or skeptical when he is personally thwarted “African dust,” and they have enabled the in his plans—when his crops are inundated meteorologist to establish as a fact, what or leveled with the ground-his forests had previously been the result of theory, shattered or uprooted—his tender frame that the north-east and south-east trade fevered with heat or with cold-and the winds, after meeting and rising up in the circle which he loves smitten with famine equatorial calms, take their observed or with pestilence. And yet he ought to paths, the south-east trades passing over know, and if he does not know, he ought into the Northern Hemisphere, and the to learn, that these apparent evils are the north-east trades into the Southern Hemiworkings of that complex machine, with sphere. By examining the “sirocco or its pinions of heat and air and water, African dust,” Ehrenberg found it to conwhich feeds and sustains every living sist of infusorial animalcules, and organisms thing in the animal and vegetable world. whose habitat is not Africa but the southBut though it is not difficult to compre- east trade-wind region of South-America. hend this general truth, the philosopher In the strikingly similar specimens from is only beginning to understand some of the Cape de Verd Islands, Malta, Genoa, the simpler processes which are under our Lyons, and the Tyrol, he recognized daily observation; and we can hardly South-American forms; so that they must congratulate him on having discovered a have been carried by a perpetual upper single law which regulates the weather. current of air from South-America to While the astronomer, with his time- North-Africa. The rain-dust, which, acpiece and his telescope, can predict and cording to Humboldt, imparts a straw exhibit phenomena in the heavens invisi- color to the atmosphere, is of a brick-red ble to the human eye, the most weatherwise sage, even with the barometer and

* Jansen's Appendix to Lieut. Maury's “Physical thermometer in his hand, and the wind- Geography of the Sea,” translated from the Dutch by gage in his view, dare not, without pre- Mrs. Dr. Breed of Washington.

or yellow-ochre color when collected in immense pile and helix, which being exparcels. It falls most frequently in spring cited by the natural batteries in the sea or autumn, generally from thirty to sixty and atmosphere of the tropics, excites in days after the equinoxes; and in order to turn its oxygen, and imparts to atmoexplain this, Ehrenberg supposes that a spherical matter the properties of magnet“ dust cloud is held constantly swimming ism.” “With these lights,” he continues, in the atmosphere by continuous currents "we see why air, which has completed its of air, and that it lies in the region of the circuit to the whirl about the Antarctic retrade-winds, and suffers partial and period. gions, should then, according to the laws ical deviations.” As this dust is probably of magnetism, be repelled from the south taken up in the dry and not in the wet and attracted by the opposite pole towards season, Lieut. Maury is disposed to be the north.Although we have endeavor. lieve that it comes from one place in the ed, in a very brief space, to give our vernal, and from another in the autumnal readers some idea of our author's arguequinox.

ment in favor of a relation between the When the opposite trade-winds meet in magnetism of oxygen (not the magnetism the equatorial calms and rise up together, of the earth) and the circulation of the Lieut. Maury asks an important question. atmosphere, we can not admit that it is What makes them cross? What is the either consistent with fact or sound in power which guides the northern trade to theory. Whatever it be which constithe south, and the southern to the north ? tutes “the magnetism of the earth,” we And he proceeds to answer it in his sixth must look to it as the origin and regulator chapter, “On the probable relation be- of any magnetic action which may be found tween magnetism and the circulation of to exist upon the currents in our atmothe atmosphere.” The theory which our sphere.* author here expounds is founded on the From the currents of the atmosphere fine discovery of Dr. Faraday, that oxygen our author passes to the currents of the gas, which forms one fifth part of the sea, and he sets out with the assumption, atmosphere, is magnetic; that its magne“ that from whatever part of the ocean a tic force is diminished with heat, and that current is found to run to the same part, the atmosphere is a magnetic medium a current of equal volume is found to ever varying in its magnetic power by the return.” It is not necessary that the ocean influence of natural circumstances. From currents run, like our rivers, from a higher theory, and some observations by Passy to a lower level. While some run on a and Bellot, he conceives that the atmo- level, others, like the Gulf Stream, actualspherical nodes or calm regions, or poles ly run up hill

. The currents from the of the wind, * are coïncident with the north Atlantic to the Mediterranean, and from and south magnetic poles, and also with the Indian Ocean into the Red Sea, run the poles of maximum cold discovered by down hill. In order to explain this, in the Sir David Brewster ;t and he considers case of the Red Sea, the surface of which that there is such a physical connection is an inclined plane, Lieutenant Maury among these three poles as to indicate a supposes its channel to be dry, smooth, corresponding relation between magnetism and the circulation of the atmosphere.

* In support of the doctrine of the crossing of the “So wide,” says he, “is the field of specu- air in the Equatorial Calm Belts, Lieutenant Maury lation presented by these discoveries, that adduces the fact, stated by Lieutenant Jansen and we may, in some respects, regard' this Dr. Moffat, that ozone is most abundant in the Northgreat globe itself

, with its cusps, and ern Hemisphere in winds that have Southing in spiral wires of air, earth, and water, as an have Northing in them; and, supposing that this

them, and in the Southern Hemisphere in winds that remarkable substance is the production of thunder

and lightning, he presumes that it may be generated * Professor Coffin has been led, by numerous ob- among the detonations and clouds and rains of the servations, to place his "meteorological pole," or Equatorial Calms." If this be its origin, he then pole of the winds, in Lat. 104° North and Long. | asks, how it “can cross the trade-wind regions ex105o West, coinciding nearly with the pole of maxi- cept with the upper currents ?" We can not answer mum cold. See " Smithsonian Contributions to this and other analogous questions which he very Knowledge,” vol. vi., p. 854.

ingeniously puts; but, with all the respect which we + See

Edinburgh Encyclopædia," Art. “Polar have for the opinions and reasonings of our author, we Regions,” by Dr. Scoresby, vol. xvii., p. 15; and are led rather to question than to maintain the doc. Encyclopædia Britannica," Seventh Edition, Art. trino which he advocates, when it requires such arguMagnetism," vol. xiii., p. 695.

ments to support it.

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