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melted material. May there not exist between from the same vicinity upon this cold current for cold and warm sea water a tendency similar in the South. Many of them loaded with earth, have some degree to that between oil and water ? See- been seen aground on the banks. This process of ing how great is the resistance encountered by the transferring deposites for these shoals has been Gulf Stream in its Eastward motion, and how in- going on for ages; and, with time, seems altogether sufficient is any head of water in the Gulf to give adequate to the effect described. it its Northward tendency, may there not exist Nay more, a geodetic examination as to the between the waters of the stream and their fluid course of the Gulf Stream, does not render it by banks, always heaving and moving to the swell of any means certain that it is turned aside by the the sea, a sort of peristaltic force, which, with Grand Banks of Newfoundland at all ; but that, other agents, assists to keep up and preserve this in its route from the coasts of Georgia as far towonderful system of ocean circulation ? We know wards the shores of Europe as its path has been that undulatory motion varies with temperature in distinctly ascertained, it describes the arc of a certain other substances, and why should it not great circle as nearly as may be. Following the line vary in water also ?
of direction given to it after clearing the Straits of Sir Isaac Newton has demonstrated, that the Florida, its course would be nearly on a great circle velocity of waves is in the subduplicate ratio of passing through the poles of the earth. That it their breadths. Therefore, if two vessels in a calm, should be turned from this and forced along one one in, and the other outside of the Gulf Stream, inclining more to the East, requires, after it leaves would each count the waves that pass, or the times these strails, the presence of a new force to give that the vessel rolls from side to side, in any given it this Eastward tendency. And have we not pretime, we should have an argument for determining cisely such a force in the rate at which different whether the oscillation of a wave in the Gulf parellels perform their daily rounds about their axis ? Stream, be shorter or longer, whether its rise and in consequence of this, the stream, when it first fall be greater or less, or whether there be any dif- enters the Atlantic from the Gulf, is carried with ference whatever between a warm wave and the cold the earth around its axis at the rate of two miles one from which it is generated. That the waters and a half the minute faster towards the East than of the Gulf Stream are more troubled than those it is when it sweeps by the Grand Banks of Newof the Atlantic we all know from the "ugly seas," foundland. which Navigators so much complain of there. That this explanation as to its Eastward tenAlmost the last, if not the very last word heard dency should hold good, a current setting from the from the unfortunate schooner Grampus, was con- North towards the South, should have a Westward tained in a letter stating how greatly that vessel tendency. Accordingly, and in obedience to the was distressed by them.
propelling powers, derived from the rate at which But it is facts and not theory that we want. We different parallels are whirled around in diurnal have not enough of the former to build up any the motion, we find the current from the North, which ory at all! Nor should I undertake the structure is meets the Gulf Stream on the Grand Banks, tawe had. In planning a system of observations in king a South-Westwardly direction, as already this magnificent field, instructions should cover the described. It runs down to the tropics by the side whole ground, and the attention of observers should of the Gulf Stream, and stretches as far to the be directed to every point from which it is possi- West as our own shores will allow. Yet, in the ble for light to come. Therefore, in throwing out face of these facts, and in spite of this force, both these suggestions, sailor like, I have but cast over Major Rennell and M. Arago make the coasts of my bottles; perhaps they may be picked up at the United States and the shoals of Nantucket to some distant day, perhaps they may never be heard turn the Gulf Stream towards the East.
The maximum temperature of the Gulf Stream In its course to the North, the Gulf Stream is 86', or about go above the Ocean temperature gradually tends more and more to the Eastward, due the latitude. Increasing its latitude 109, it loses until it arrives off the banks of Newfoundland, but 20 of temperature. And after having run 3,000 where its course is said to become due East. These miles towards the North, it still preserves, even in banks, it has been thought, deflect it from its pro- winter, the heat of summer. With this temperature, per course, and cause it to take this turn. Ex- it crosses the 40th degree of North latitude, and amination will prove, I think, that they are in part there, overflowing its liquid banks, it spreads itself the effect, certainly not the cause. It is here, that out for thousands of square leagues over the cold wathe frigid current already spoken of, with its ice- ters around, and covers the ocean with a mantle of bergs from the North, are met and melted by the warmth that serves so much to mitigate in Europe warm waters from the Gulf. Of course the loads the rigors of winter. Moving now more slowly, of earth, stones and gravel brought down upon them but dispensing its genial influences more freely, it are here deposited. Captain Scoresby, far away finally meets the British Islands. By these it is in the North, counted 500 icebergs selling out'divided, one part going into the polar basin of
Spitsbergen, the other entering the Bay of Biscay, circulation, the peculiar features of the surroundbut each with a warmth considerably above Oceaning country assure us we should have the hottemperature. Such an immense volume of heated test, if not the most pestilential climate in the water can not fail to carry with it beyond the seas world. As the waters in these two cauldrons bea mild and moist atmosphere. And this it is which come heated, they are borne off by the Gulf Stream, so much softens climate there.
and are replaced by cooler currents through the We know not what the depth or the under tem- Caribbean Sea; the surface water, as it enters perature of the Gulf Stream may be. But assu- here, being 30 or 4°, and that in depth, 40of cooler ming the temperature and velocity at the depth of than when it escapes from the Gulf. Taking this 200 fathoms, to be those of the surface,* and taking difference in surface temperature only, as the dethe well-known difference between the capacity of
gree of heat accumulated there, a simple calculaair and of water for specific heat, as the argument, tion will show, that the quantity of specific heat a simple calculation will show, that the quantity of daily carried off by the Gulf Stream from those heat discharged over the Atlantic from the waters regions, and discharged over the Atlantic, is of the Gulf Stream in a winter's day, would be sufficient to raise mountains of iron from zero sufficient to raise the whole column of atmosphere to the melting point, and to keep up from them that rests upon France and the British Islands, a molten stream of metal greater in volume than from the freezing point to summer heat.
the waters daily discharged from the MissisEvery West wind that blows, crosses the stream sippi river. Who, therefore, can calculate the on its way to Europe, and carries with it a portion benign influences of this wonderful current upon of this heat to temper there the Northern winds the climate of the South? “Cui bono?" In the of winter. It is the influence of this stream upon pursuit of this subject, the mind is led from nature climate, that makes Erin the “ Emerald Isle of
up to nature's God. Who, therefore, in this Christhe Sea,” and that clothes the shores of Albion tian land, shall repeat the question? Or whose with evergreen robes ; while in the same latitude mind will the study of this subject not fill with proon this side, the coasts of Labrador are fast bound fitable emotions? Unchanged and unchanging alone, in fetters of ice. In a valuable paper on currents,t of all created things, the Ocean is the great emMr. Redfield states, that in '31, the harbor ofblem of its everlasting Creator. He “ treadeth St. John's, Newfoundland, was closed with ice as upon the waves of the sea," and is seen in the wonlate as the month of June ; yet, who ever heard of ders of the deep. Yea, “he calleth for its waters, the port of Liverpool, on the other side, though and poureth them out upon the face of the earth." 20 further North, being closed with ice, even in In obedience to this call, the aqueous portion of the dead of winter? The Baron Humboldt's iso- our planet preserves its beautiful system of cireuthermal curves show that the genial influence of
lation. By it, heat and warmth are dispensed to this current is felt in Norway, and even on the the extra-tropical regions; clouds and rain are sent shores of Spitsbergen in the polar basin. The to refresh the dry land; and by it, cooling streams mere sweeping of the winds over a large tract of are brought from Polar Seas to temper the heat of ocean without any such warm stream, is not suffi- the torrid zone. At the depth of 240 fathoms, the cient to produce such effects upon climate as is temperature of the currents setting into the Caribfully shown by comparing the climate of Spitsber-bean Sea has been found as low as 48°, while that gen with that of places similarly situated in the of the surface was 85°. Another cast with 386 South Sea with regard to winds and water, but fathoms gave 43° against 83o at the surface. The not with regard to currents.
hurricanes of those regions agitate the sea to great Nor do the beneficial influences of this stream depths : that of 1780 tore rocks up from the bottorn upon climate end here. The West Indian Archi- in 7 fathoms, and cast them on shore. They therepelago is encompassed on one side by its chain of fore can not fail to bring to the surface portions of islands, and on the other by the Cordilleras of the the cooler water below. Andes bending through the Isthmus of Darien and
These cold waters doubtless come down from stretching themselves out over the plains of Central the North to replace the warm water sent through America and Mexico. Beginning on the summit the Gulf Stream to moderate the cold of Spitsberof this range, we leave the regions of perpetual gen; for within the Arctic Circle, the temperature snow, and descend first into the tierra témplada, at corresponding depths off the shores of that Island
, and then into the’ tierra caliente, or burning land. is only one degree colder than in the Caribbean Sea; Descending still lower, we reach both the level and while on the coasts of Labrador the temperature the surface of the Mexican Seas, where, were it in depth is 25°, or 70 below the freezing point of not for this beautiful and benign system of aqueous * Which in all probability is not the case.
+ American Journal of Science, Vol. 45, p. 293. | From the
Caribbean Surface temp. 830 Sept., 84° July, 830 journals of
861° Mosquito Coast. Mr. Dunsterville.
Sea. ŠTemp. in depth 489, 240, faths. 43°, 386 faths. 42°, 450 faths. 43. 500 faths.
found to grow.
fresh water. Capt. Scoresby relates, that on the her choicest fish. The same is the case in the coast of Greenland, in latitude 720, the tempera- Pacific. A current of cold water from the South ture of the air was 42°—of the water 34°, and 29° sweeps the shores of Chili, Peru and Columbia, at the depth of 118 fathoms. He there found a and reaches the Gallipagos Islands under the line. current setting to the South, and bearing with it Throughout this whole distance, the world does not this extremely cold water, with vast numbers of afford a more abundant or excellent supply of fish. icebergs whose centres, perhaps, were far below Yet, out in the Pacific, at the Society Islands, zero. It would be curious to ascertain the routes where coral abounds, and the water preserves a of these under currents on their way to the tropi- higher temperature, the fish, though they vie in cal regions, which they are intended to cool. One gorgeousness of coloring with the birds, and plants, has been found at the equator 200 miles broad and and insects of the tropics, are held in no esteem 230 colder than the surface water. Unless the as an article of food. I have known sailors, even land or shoals intervene, it no doubt comes down after long voyages, still to prefer their salt beef in a spiral curve.
and pork to a mess of fish taken here. Therefore, Perhaps the best indication as to these cold cur- let those who are curious as to the migratory habits rents may be derived from the fish of the sea. The of fishes, join hands in the proposed system of whales first pointed out the existence of the Gulf observations upon currents--for the few facts Stream by avoiding its warm waters. Along our which we have bearing upon the subject, seem to own coasts, all those delicate animals and marine suggest it as a point of the inquiry to be made, productions which delight in warmer waters are whether the habit of certain fish does not indicate wanting; thus indicating by their absence the cold the temperature of the water; and whether these current from the North now known to exist there. cold and warm currents of the Ocean, do not conIn the genial warmth of the Sea about the Ber-stitute the great highways through which migramadas on one hand and California on the other, tory fishes travel from one region to another. we find, in great abundance, those delicate shell Navigators have often met with vast numbers of fish and coral formations which are altogether want- young sea-nettles (medusa) drifting along with the ing in the same latitudes along the shores of South Gulf Stream. They are known to constitute the Carolina. The same obtains in the West coast of principle food for the whale; but whither bound South America ; for there, the cold current almost by this route has caused much curious speculation ; reaches the line, before the first sprig of coral is for it is well known that the habits of the whale
are averse to the warm waters of this stream. An A few years ago, great numbers of bonita and al- intelligent sea captain informs me, that two or bercore-tropical fish—following the Gulf Stream, three years ago, in the Gulf Stream on the coast entered the English Channel, and alarmed the fish- of Florida, he fell in with such a “school of young ermen of Cornwall and Devonshire, by the havoc sea-nettles as had never before been heard of.” which they created among the pilchards there. The sea was covered with them for many leagues.
It may well be questioned if our Atlantic cities and He likened them, in appearance on the water, to towns do not owe their excellent fish markets, as acorns floating on a stream. But they were so well as our watering places, their refreshing sea thick as completely to cover the sea. He was bathing in summer, to this stream of cold water. bound to England and was five or six days in sailThe temperature of the Mediterranean is 40 or 50 ing through them. In about sixty days afterwards, above the Ocean temperature of the same latitude, on his return, he fell in with the same school off and the fish there are very
indifferent. On the the Western Islands, and here he was three or four olher hand, the temperature along our coast is days in passing them again. He recognized them several degrees below that of the Ocean, and from as the same, for he had never before seen any like Maine to Florida our tables are supplied with the them; and on both occasions he frequently hauled most excellent of fish. The sheeps-head, so much up buckets full and examined them. esteemed in Virginia and the Carolinas, when taken Now the Western Islands is the great place of on the warm coral banks of the Bahamas, loses its resort for whales; and at first there is something favor and is held in no esteem. The same is the curious to us in the idea, that the Gulf of Mexico case with other fish: when taken in the cold water is the harvest field, and the Gulf Stream the gleaner of that coast, they have a delicious flavor and are which collects the fruitage planted there, and conhighly esteemed; but when taken in the warm veys it thousands of miles off to the hungry whale water on the other edge of the Gulf Stream, though at sea. But how perfectly in unison is it with the but a few miles distant, their flesh is soft and unfit kind and providential care of that great and good for the table. The temperature of the water at Being which feeds the young ravens and caters for the Balize reaches 90°. The fish taken there are the sparrow! not to be compared with those of the same latitude Our information as to the Sargasso Sea is most in this cold stream.
New Orleans therefore re- barren. Whence comes the weed with which it is sorts to the cool waters on the Florida coasts, for 'covered, or where its place of growth may be, is matter of dispute among learned men. But as for The contemplated system of observations will the office which it performs in the economy of the be of high interest also to the meteorologist, whose Ocean, conjecture even is almost silent. Certain it science at this time is attracting so much attention. is however, that that sea of weeds was not planted The fogs* of Newfoundland, which so much endanin the middle of the Ocean without design. The ger Navigation in winter, doubtless owe their er. marks of intelligence, displayed throughout the istence to the presence, in that cold sea, of imwhole system of terrestrial adaptations, forbid the mense volumes of warm water brought by the idea. Botanists tell us of certain“ nodding flowers" Gulf Stream. Sir Philip Brooke found the air on which, at a certain stage of growth, bend their each side of it at the freezing point, while that of heads, that the dust from the anthers may fall upon its waters was 80°. “ The heary, warm, damp the stigma; when the necessary impregnation is air over the current produced great irregularities accomplished, they become again erect. Now it in his chronometers.” The excess of heat daily is clear, if the stalk were stronger or weaker, if brought into such a region by the waters of the the force of gravity, or the size of the earth were Gulf Stream, if suddenly stricken from then, greater or less, this operation could not take place, would be sufficient to make the whole column of the flower would not yield seed after its kind, and superincumbent atmosphere ten times hotter than the species must become extinct. Such is the deli- melted iron. cate snow-drop of our garden walks. Therefore, With such an element of atmospherical disturat creation, when this little flower was put forth, bance in its bosom, we might expect storms of the the mass of the earth and the force of gravity most violent kind to accompany it in its course. must have been taken into account.
Accordingly, the most terrific that rage on the “There is something curious,” says Professor Ocean have been known to spend their fury in and Whewell, and he might have added profitable and near its borders. instructive too, “in thus considering the whole Our nautical works tell us of a storm which mass of the earth, from pole to pole, and from cir- forced this stream back to its sources, and piled cumference to centre as employed in keeping a up the water in the Gulf to the height of 30 feet. snow-drop in the position most suited to its vege- The Ledbury Snow attempted to ride it out. When table health.” How much more forcibly must this it abated, she found herself high up on the dry adaptation and the necessary terrestrial arrange- land, and discovered that she had let go her anchor ments apply to this sea and to the Gulf Stream, anong the tree tops on Elliott's Key. The Flopeopled, as no doubt they are, with myriads and rida Keys were inundated many feet, and the scene myriads of living creatures ! Even as to the depths presented in the Gulf Stream was never surpassed of this sea we are ignorant; and as to the animals in awful sublimity on the Ocean. The water thos which the Gulf Stream conveys from one part of dammed up, is said to have rushed out with wonthe Ocean to another, observation has told us scarcely a word. This is a fit subject of inquiry, * The dampness of the climate in England, as well as and comes within the scope and reach of the plan that here when Easterly winds prevail, is attributable also proposed.
to the Gulf Stream. * The Sargasso sea is an immense pool, in which are to the manner and the means by which pature collected in gathered in great quantities, gulf weed, drift wood, wrecks, her store houses the coal measures of the mountains. and all the floating substances cast upon the Atlantic. This weed is not strewed over the sea in an unbroken Waters from the Indian ocean, by the Lagullas current- sheet ; it is arranged in seams and longitudinal sections from the frozen regions beyond Cape Horn, through the corresponding to the layers of coal in the coal basin. The ice-bearing current from the Antartic seas-waters from sea is even free, in a great degree, from storms, and if we the Arctic Ocean, through the Labrador current-all find imagine that these weeds in the process of time, gradually their way into the Atlantic, and deliver whatever floating wither, contract and sink, we shall have here a beautiful substances they bear, up to the Gulf Stream-whence, illustration as to the manner in which the coal searos were like the fucus natans, gradually finds its way into this arranged in layers as we now see them among the moai weedy sea, which is a basin in the Atlantic, between the tains. Cape de Verds, Canaries, and Western Islands, quite equal The bowsprit of the “ Little Belt,” lost in the West loin extent to the Mississippi valley.
dies, was found not long afterwards near the edge of the Three hundred and fifty years ago, Columbus passed Sargasso. over this sea. It was then covered with weeds, as it now In a former voyage, I once met upon its horders a rough is, and as it no doubt had been for ages and ages before. spar of yellow pine, probably grown in one of our Southern What its depth, or the character of the bottom may be, we States. It was covered with a beautiful crop of analifae, know not-we are even ignorant as to the place of growth interspersed with crabs, and surrounded by a school of for its weeds. Yet to the geologist, this is a volume brim dolphin. It had evidently been in the water a great whit, full of unread studies and mysterious things—it is a type for it was so water-soaked, that the wood had become transon a grand scale, of the gathering together the materials lucent-almost as much so as thin slips of very " fat” light for his ancient coal formations-and to such an one, the wood. Receiving a still heavier load of barnacles and round world no where else affords a parellel. It is the molluscs, it would in time have reached this sea, and been only page any where to be found, where time, with his borne down to the depths below with its load of ishatieverlasting characters, is now writing his commentary as'tants, there, before the next hour, be marked on the geoda
derful velocity against the fury of the gale, produ- / and the waves rose to such a height that forts and cing a sea that beggared description.
castles were washed away, and their great guns The great hurricane of 1780 commenced at carried many yards; houses were blown down, Barbadoes. In it, the bark was blown from the ships were wrecked, and the bodies of men and trees, and the fruits of the earth destroyed ; the beasts lifted up above the earth and dashed to pieces very bottom and depths of the sea were uprooted, in the storm. At the different islands not less than gical time-piece, to be elaborated into the most beautiful volcanic; and but a few years ago, as if in warning, or to and rare among fossils.
give note as to the state of preparation below, an island was This basin is the great centre and receptacle of Atlantic cast up from the bottom, to sink again in this very sea. dist. The moss and the lichen of the extreme North, But while the currents of the sea in one place are busied brought down to the Grand Banks, are handed over on ice with the work of collecting and hiding in the middle of the bergs to the Gulf Stream, to be borne on towards this cen- ocean this vast assemblage of vegetable remains, they are tral whirl and lodged by the side of the larch and the fir of employed on the out-skirts in collecting and arranging the the farthest South, conveyed also by the ice-bearing* cur- materials for a formation of quite another sort. The ice-bear. reits from Cape Horn. There too, in the caverns below, ing currents from the North and the South bring down iceare to be found the flora and vegetables, with land shells, bergs laden with earth, boulders and the carcasses of aniinsects, etc., borne along with the drist wood from the river mals, to be deposited at one place upon the Grand Banks Gambia and the coast of Africa, from the Amazon and the of Newfoundland, and at the other upon the Lagullas banks Oronoco, the upper Missouri and lower Mississippi. In of South Africa. These are the places at which nature bids short, by reason of these currents and this sea of weeds, the tepid currents of the torrid zone to meet the icebergs we have before our eyes the means of grouping in that from either pole, and to relieve them of their frigid loads of basis, the most extended, varied, and magnificent collec. rocks and gravel. Are there not similar banks, at greater tion of vegetable and animal matter that is known in any or less depth, near the junction of every ice-bearing curof the formations that have yet become geological.
rent, with its equatorial counterpart? Tihat the drift wood from these regions should not be Geology, through its mineral wealth and interests, it has more often met with at sea, is not at all surprising. Barely been said, is at the bottom of the anti-corn law league in floating at best, the prolific waters of the Gulf Stream soon England. It certainly has something to do with the tariff lead the floating trees with immense numbers of barnacles doctrines of Pennsylvania ; for without the iron and the and shell fish. Many of them possess the power of expan. coal of that and other States, legislators would argue less sion in a greater or less degree, and by a sort of concert of the question of home industry, tariff and protection. The action, such as we see among corals and other fish, may learned chairman of this association had occasion a few possess the power of floating their shifting domicil at any weeks ago to point out the connection between geology and depth. Finally reaching the Sargasso sea, the temperature experiments upon the ballistic pendulum.* This all perof the water and other conditions become unfavorable to vading science, through the currents of the sea, is quite as their animal health ; they die, and thus the weight of the closely allied to navigation as, through the mineral wealth shells is sufficient to carry the whole tree, with its branches of the land, it is to legislation, custom-house laws, and entire, down to the lower deposits, and place it there in the Government revenue. Whose pursuits would seem to be most gentle manner.
farther apart than that of the geologist among the cliffs of This
process requires a very short time; hence it is, that the hills and the outcrops of the valleys, and that of the boating drift-wood has not been met with in larger quanti- mariner among the billows of the sea ? Meeting on the crest lies in tbis sea. But some idea may be derived of the of two waves, they join hands across the Gulf Stream; the quantity of drift which is thus conveyed, from the fact, that weedy sea" is common ground, and the iceberg a volume be place of light house keeper at the Tortugas islands is of classic lore and high import ; to one it is a type of ancient bonsidered one of the most profilable on account of its jet- formations, to the other an index pregnant with meaning. am. The value of the copper and lead to be collected In short, the facts collected by one are to the other points roun the fragments of boats wrecked on the Mississippi, and of the most valuable information. Insted on the Tortugas, is considered by the keeper quite The line of meeting between the waters of the Gulf squal to his salary from the Government. Now these islands Stream and the Atlantic is distinct to the naked eye for Te on the very edge of the stream, and the materials from several hundred miles. This unreadiness of cold and tepid trecked boats bear but a small proportion to the drift-wood sea-water to commingle has been often remarked upon, and rought down that river. Let therefore the imagination seems to impart to one current the power of dividing and Keture the mass of materials, that in the process of ages turning others aside. Thus the Gulf Stream bifurcates the pon ages would be thus transported from the Mississippi Labrador current, one part of which underruns the Gulf alley, from the plains of the Oronoco and the head waters Stream, and the other takes a southwestwardly direction ( the Amazon, from the banks of the St. Lawrence and along the coast. be forests of Africa, from central America, the West In- The reverse happens with the current from the Indian ies, and shores of Labrador, into the Sargasso sea. ocean, of which the Lagullas is a part. Here the cold curThis sea can be looked upon in no other light than as the rent divides the warm one-one branch of which, as the ere of a future coal basin or peat bog, in which, at sume Lagullas, after passing the Cape of Good Hope, is even note day, when we perhaps shall have become fossils. turned back towards the northwest, while the other, the bd this part of the sea dry land, olher geologists will roam, Australian, pursues its natural course to the southward daire, speculate and dispute. Indeed, it requires but and eastward, passing the island from which it takes its Itle stretch of the imagination to conceive that nature, name. lith her corps of earthquake sappers and volcano miners, Perhaps it was upon the tail of this or some other equa
now at work there, laying her train for a grand geological isplay of uplift and heave. Teneriffe and the Azores are * In his paper before the National Institute, Captain Mor
decai stated, that the sand used as a core in the pendulum * I have seen icebergs borne up on this current into the had been compressed by impact from the ball, so as to adouth Atlantic as far North as lat. 37° S.
here and present the appearance of sand-stone.