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of nations, which even despotism can not appropriate, and as an essential part of the complex terraqueous apparatus which constitutes "The Life of the Earth."

"THE GEOGRAPHY OF THE SEA."- its nobler phase, as the common highway What an incongruous idea do these words present to the scholar! How thoroughly incomprehensible by the ordinary mind! Considering the ocean as but the great reservoir for receiving the superfluous waters of the earth, as the nursery of the whale and its congeners, or as the dreaded grave of the seafaring man, we have seldom regarded it under

The Physical Geography of the Sea. By M. F. MAURY, LL.D., U.S.N., Superintendent of the National Observatory. An entirely New Edition (6th,) with Addenda. New York, 1857. With 13 Plates, pp. 384.

Maury's Sailing Directions. 7th Edition. Febru-
ary, 1857. Pp. 870.
Report of the Meteorological Department of the
Board of Trade, 1857.

First and Second Reports of the Liverpool Com

Humboldt has given this name to what he justly regards as a new department of science. VOL. XLIV.-NO. IV.

From the earliest times, before the sailor trusted himself to the open sea, a certain degree of knowledge of the tides and the winds was required for the safe navigation of his shores; but when he adven

pass Committee to the Board of Trade, with Letters from the ASTRONOMER ROYAL thereupon. London, 1857.

Instructions for Correcting the Deviation of the Compass. Edited by ARCHIBALD SMITH, Esq., M.A., F.R.S., late Fellow of Trinity College, Cambridge. London, 1857.

Swinging Ships for Deviation. London, 1857. Weather Book; Abstract of Log and Meteorological Register. Issued by the Board of Trade.

First Number of Meteorological Papers. Published by Authority of the Board of Trade. London, 1857 Wind Charts. Published by the Board of Trade.


tured across the Atlantic, or into the bo- | of which the sea is the nursery and the som of the Indian and Pacific Oceans, or grave. A brief history, therefore, of what attempted to circumnavigate the globe, has already been accomplished in this and reach its ice-bound poles, seamanship great enterprise, may be useful to some more advanced, and science more pro- of our readers, and we trust may be made found, were required. The currents in interesting and instructive to all. the atmosphere, the trade winds and monsoons, the belts of calm, tropical and equatorial, the hurricanes and tornadoes of the torrid zone, the thunder storms, and the air and water-spouts of southern climates, perpetually distract the mariner in his course, and demand from him all the skill which can be derived from science and experience. Nor are the currents of the ocean less amenable to inquiry, and less formidable to the seaman than those of the atmosphere. The two Gulf Streams of the Northern and Southern Hemispheres, the currents from the Poles to the Equator, and from the Equator to the Poles, and the bores and tidal waves of the East, perform important fuuctions in our terraqueous world, and are only now revealing to science their origin and their laws.

It would be a difficult task, and one not necessary to our present purpose, to give an account of the delays and dangers to which the navigator is exposed in those remote seas which have been comparatively little visited by European or transatlantic communities. It will be sufficient to refer to the Atlantic Ocean, the great common of civilization, which is covered, at every season of the year, with thousands of vessels, intercarrying the produce of the old and new worlds, and freighted with so many precious lives. The grand and peculiar feature of the Atlantic is the GULF STREAM, which till recently has been regarded by the seaman as a serious obstruction in his course. Ig norant of its strength and limits, his vessel was often drifted many miles out of its course, and the length of his voyage The study, therefore, of the sea, of its greatly extended.* Before the high temgeography, its movements, and its physi-perature of this current was ascertained, cal condition, while it presents to the general reader topics at once popular and instructive, affords to the philosopher a rich and boundless field of research, and must eventually promote the highest interests of humanity and civilization. As a new department of science, it has already excited the notice of every nation in the Old and New World; and societies and governments are actively employed in promoting the various inquiries which it demands, in order to shorten the voyages to distant lands, to guard life and property which are risked at sea, and to advance those branches of knowledge which are associated with winds and waves, and embrace that profusion of life" make his port," he is driven back from

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a voyage from Europe to New-England and New-York, and even so far south as Cape Chesapeake, was both difficult and dangerous. In approaching the American coast, vessels were beset by snow storms and gales, which baffled the strength and skill of the seaman. His bark became a mass of ice, her crew frosted and helpless, and "she remained obedient only to her helm, and was kept away for the Gulf Stream." On reaching its edge, she passed from a wintry sea into one at summer heat. The ice disappeared from the ship, and "the sailor bathed his stiffened limbs in the tepid waters of the stream;" but in attempting again to

the north-west, and exposed to the dangers which he had surmounted. In gales of this kind many ships annually founder; and there are numerous instances in which vessels, with their crews enervated in tropical climates, have encountered, near the capes of Virginia, snow-storms which have driven them back, again and again, into the Gulf Stream, and prevented them from

* In his passage a few years ago from Sierra Leone to New-York, General Sabine was drifted, 1600 miles off his way by the force of currents alone.

great certainty, and in the event of hazy weather, as to his position." Although this important discovery was made in 1775, it was not generally made known

making an anchorage, for fifty or sixty days. In mid-winter, the number of wrecks and the loss of life, along the Atlantic sea front, was frightful. Sometimes, in the month's average, the wrecks till 1790, when Dr. Franklin published amounted to three a day; and vessels which escaped this calamity, were blown off and obliged to take refuge in the West-Indies, where they remained till spring, before they could venture to approach the inhospitable coast.

The Gulf Stream, to which these calamities were due, has, by the agency of science, become a boon to navigation. In 1770, when Dr. Franklin was in London, he learned the curious fact, that the Falmouth packets to Boston arrived a fortnight later than the trading vessels from London to Rhode Island, although the distance was much less. Captain Folger, a Nantucket whaler, then in London, explained to the Doctor this singular anomaly. The Rhode Island captain was acquainted with the high temperature and great velocity of the Gulf Stream, and turned it to account, not only as a refuge from the snow-storms, and as a land-mark or beacon for the coast in all weathers, but as a means of shortening their voyage. The English captains, ignorant of the properties of the current, kept their ships in it, and were set back sixty or seventy miles a day. Dr. Franklin viewed the discovery of the high temperature of the Gulf Stream as of such importance that he ungenerously, we think, kept it a secret, as if it was a solution of the great problem of finding the longitude at sea, for which a reward, similar to that given to Harrison, might be claimed.* Vessels having often been 5° and even 10° out of their reckoning, it was naturally thought to be a solution of the problem of the longitude, "for, on approaching the coast," as our author observes, "the current of warm water in the Gulf Stream, and of cold water on this side of it, if tried with the thermometer, would enable the mariner to judge with

* Mr. Maury says that Dr. Franklin concealed his discovery for a while "through political considerations;" but his observations on the longitude problem indicate clearly that the motives of the Doctor must have been of a personal kind, for no consideration could be called political which withheld from the American navigator the means of saving himself from shipwreck, and from the American merchant the rapid and safe conveyance of his


his work on Thermometrical Navigation. Its beneficial employment in navigation was immediate. The northern ports of America were as accessible in winter as in summer; and there seems to be no doubt that it was then the cause of the great decline which took place in the trade of the two Carolinas, "Charleston, the great southern emporium of that day, being removed from its position as a halfway house, and placed in the category of an outside station."

In consequence of the great boon obtained for navigation by the study of the Gulf Stream, Lieutenant Maury, a distinguished officer in the United States Navy, was led to collect from the captains of the mercantile marine all the facts which they had observed respecting the winds, tides, currents, and temperature of the ocean. After a careful examination of them, he published the results at which he arrived, in his volume, entitled "The Wind and Current Charts," a work which has, to an extraordinary extent, shortened and rendered safe voyages that had always been long and perilous. By the use of his charts and sailing directions, the average passage from England to Australia has been reduced from 125 to 97 days, the homeward passage having been once made in 63 days! The passage from New-York to California has, in like manner, been reduced from 183 to 135 days. The benefits thus conferred on every maritime nation were so obvious, that their respective governments, at the desire of Lieutenant Maury, were induced to take an interest in the subject, and to send qualified persons to discuss it at a general conference. Representatives from England, France, Russia, Sweden, Norway, Holland, Denmark, Belgium, Portugal, and the United States, accordingly met in Brussels on the 23d August, 1853, and adopted a system of observations to be made on board all their vessels. Spain, Prussia, Sardinia, the Holy See, Austria, Brazil, the republics of Bremen and Chili, and the free city of Hamburgh, subsequently offered their coöperation in the same plan; and the sea is now crowded with observers, who will carry on their researches in war as well as in peace. In

the event of any of these vessels being | importance, and one which can not fail to captured by an enemy, it has been ar- interest and to instruct every class of ranged that the journal containing the readers. observations, shall be held sacred; and we trust that this union of nations to promote the common interest of humanity and commerce may lead to a more glorious combination to cultivate only the arts of peace. In reducing to law the elements which disturb the ocean, and in subjugating the rebellious powers which are so fatally at play in the physical world, there is work enough to exhaust all the resources of the state, and to call forth all the skill and heroism of its servants. In this peaceful strife, where conquests more valuable than kingdoms are the prize, the command to love our neighbor is never broken, and fame, the reward of victory, is as enduring as time and as noble as virtue.

After the Report of the Brussels conference had been laid before Parliament, a grant of money was made for the purchase of instruments, and the discussion of observations, and a department of the Board of Trade, under Rear-Admiral Fitzroy, was charged with the important task of carrying into effect the contemplated arrangements. In order to assist the officers of the navy and the ship-masters who may agree to cooperate in this great work, forms of abstract logs have been prepared for men-of-war and merchantmen; and those who shall keep a journal of observations and results, and send an abstract of it to the National Observatory at Washington, will be furnished, free of cost, with a copy of Lieutenant Maury's Sailing Directions, and such sheets of the chart as relate to the cruising-ground of the cooperator. The American ship-masters entered warmly into these views; and in a short time the captains of more than a thousand floating observatories were engaged day and night, in every part of the ocean, in making and recording their observations. Since the meeting of the Brussels conference, it has been proposed to extend this system of observations, to the land, and thus to obtain from every inhabited part of the globe, a series of simultaneous observations on the weather, which can not fail to advance the agricultural and sanitary interests of nations.

Our readers will understand from these details how Lieutenant Maury was led to compose his treatise on the Physical Geography of the Sea-a work of European

After giving a description of the Gulf Stream, one of the most remarkable phenomena in the ocean, he treats, in eighteen chapters, of the influence of this great current on the climates of the north of Europe and America; of the atmosphere, with its storms, its land and sea-breezes, its winds, and their geological agency; the relation between the circulation of the atmosphere and magnetism; the currents, salts, and depths of the ocean; the equatorial cloud-ring and color belts; the red fogs and sea-cloud; the climates of the ocean; the drift of the sea; the routes across it; the basins of the Atlantic; and the open sea in the Arctic regions.

The Gulf Stream is a river in the ocean, which never overflows in the mightiest floods, and is never dried up in the severest droughts. Its current consists of warm, and its banks and bottom of cold, water. It has its origin in the Gulf of Mexico, and its embouchure in the Arctic Seas. Though a thousand times greater in volume, it flows with a velocity greater than the Mississippi or the Amazon. The color of the stream is indigo blue;* and so definite is its line of junction with the common sea-water, that one half of a ship may be in blue, and the other in colorless, water.

The cause of the Gulf Stream has long been a problem among hydrographers; and even with all the light that Lieutenant Maury has thrown upon it, we can hardly consider it as solved. Dr. Franklin was of opinion that the Gulf Stream is the escaping of the waters that are constantly forced into the Caribbean Sea by the trade winds; and that the water thus pressed up, as it were, into a head, gives the current its velocity. While Lieutenant Maury admits it as a fact, that the trade

*As the Gulf Stream contains 4 per cent of salt, a larger quantity than common sea water, Lieutenant Maury is of opinion that its indigo blue color is owing to this cause. The same observer, however, who measured the saltness of the Gulf Stream, found that there was 4 per cent of salt in the sea of the trade wind regions; but we are not told that the blue color is there more rich and intense. We believe that blue is the color of pure water, and is not produced by the salt which it contains. The green color of other seas arises from the yellow produced by vegetable matter. There is no more salt, if any at all, in the blue Rhone, than in the green waters of the Rhine.

extremity of Newfoundland, being in lat. 40° 30' in winter, and in lat. 45° 30′ in September, when the sea is hottest. This oscillatory motion arises from the inequal density of the waters on each side of itat one time pressed to the right, and at another to the left, according to the seasons of the year, and the consequent changes of temperature in the sea.


The great mass of water which constitutes the Gulf Stream, has a variety of temperatures. The hottest portion is at or near the surface, the heat diminishing downwards to the bottom of the current, which never reaches the bottom, there being always a curtain of cool water between the stream and the solid earth beneath. The object of this arrangement, according to Lieutenant Maury, is to carry the stream warm to France, Great Britain, and the west of Europe, by making it pass over the non-conducting cold water at the bottom. Had the stream rushed over the solid crust of the earth, which is comparatively a good conductor, it would have lost much of its heat before it reached the west of Europe, and, we may add, it would have been greatly obstructed in its motion. We can hardly agree with our author, when he says, "that, but for this arrangement, the soft climates of both France and England would be as that of Labrador, severe in the extreme, and icebound."

winds skim the Atlantic of the water that | northern limit, as it passes the south-east has supplied them with vapor, and thus drive a salter current into the Caribbean Sea; he regards the causes as unknown why it escapes by the channel of the Gulf Stream in preference to any other. In addition to the action of the trade-winds, he conceives that there are two causes in operation which may explain the Gulf Stream-one the increased saltness of the water driven into the Caribbean Sea, and the other the small quantity of salt in the Baltic and Northern Seas. The heavy or salter water, will therefore flow into the region where it is fresher and lighter. But the temperature of the Gulf Stream is often 20° and even 30° higher than that of the ocean; and as water expands with heat, the difference of weight produced by difference of saltness may be thus more than compensated, and the waters of the Gulf Stream be lighter than those of the ocean. If lighter, then they must occupy a higher level than the waters through which they flow; assuming the shape of a roof, or a double inclined plane, from which water will run down on either side-cold water running in at the bottom, raising up the cold-water bed of the Gulf Stream, and making it shallower in its progress northward. That this is the constitution of this remarkable current, has been placed beyond a doubt. Boats in or near the center, or axis, of the stream, invariably drift to one side or the other. Sea-weed (fucus natans) and drift-wood appear in large quantities on the outer edge of the stream. Very little sea-weed and drift-wood is found on the eastern edge of it; and its accumulation on its western edge, is ascribed by our author to the diurnal rotation of the earth. In its course northward, the Gulf Stream tends more and more to the east, till, at the banks of Newfoundland, it is almost easterly. Its warm waters here melt the icebergs from the Arctic seas, which deposit the rocks, the earth, and the gravel which they bore, thus forming banks at the bottom of the ocean. From this locality the stream flows, in a state of increasing expansion, to the British Islands, to the North Sea, and the Frozen Ocean, passing along the east and west coasts of Greenland, and modifying, perhaps to some small extent, the climate of these inhospitable regions. When the Gulf Stream leaves the United States, it varies its position with the seasons; its

But it is not merely in its vertical direction that the temperature of the Gulf Stream varies. The heat of the current will of course diminish from its middle to its edges, but we were not prepared to expect that it consisted of threads of warm, alternating with threads of colder water; so that, in sailing across it from America, there is "a remarkable series of thermometrical elevations and depressions on the surface temperature of this mighty river in the sea."

In treating of the influence of the Gulf Stream upon climates, our author regards it as a portion of a great heating apparatus, similar to the hot-water apparatus which is used for heating our dwellings: the Torrid Zone is the furnace, the Mexican Gulf and the Caribbean Sea the cauldrons, the Gulf Stream the conducting

Hatteras, in N. lat. 35° 13', and W. long. 75° 30′ *The temperature of the surface water at Cape is about 80°, and 57° at the depth of 3000 feet.

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