ing the vapor from the surface, concen- | of Britannia. Whilst one portion enters trate the saline materials, and send down the Straits of Dover, another glides up the drops loaded with mineral, in order the Irish Channel; and a third, sweeping that the industrious creatures may pick along the western coast of Erin, and curvout what is requisite for their work, and ing round the Shetland Islands, actually then return them aloft for a further descends the German Ocean, where it resupply? joins the advancing tide off the mouth of the Thames, as if to pay double honor to the maritime mistress of the world. And not less lingeringly than lovingly does it perform this part of its journey; for though in some stages of its progress it moves at the rate of a thousand miles an hour, it requires upwards of twenty hours to pass from Cape Clear, at the extremity of Ireland, to the Nore. It need scarcely be said that these giant billows, which follow each other from their nursery in the Antarctic Ocean at intervals of a dozen hours, are affected in their course by the obstructions they encounter. Where the Pacific, for example, is blockaded by great coral ramparts, and spotted by numerous fair islands, He of the moon can find but little scope for his burly pastime; for the tidal wave from the south can not penetrate freely unto that spacious playground. But there are circumstances under which he gambols his strength away in a striking and boisterous manner. In certain estuaries and rivers he produces those magnificent rushes of water called bores or eagres. For the full development of this phenomenon, a gradually narrowing channel and peculiar configuration of ground are required. Some of our British streams, the Severn, the Trent, the Solway Frith, for example, are favorably organized for this purpose. But it is in the Amazon and the rivers of India and China that the tidal wave, now an advancing mass, assumes its most imposing proportions. One of these eagres in the Tsien-Tsang river has been vividly described by Dr. Macgowan in a communication to the Royal Asiatic Society:

Since, then, motion is the life of the sea, many causes conspire to keep it in a state of sleepless agitation. The most notable of these is the moon. It is surely a striking fact that a puny globe, revolving at the distance of 240,000 miles from our earth, should lift the waters of the ocean and compel huge ripples to course across its surface in regular succession. The Man in the Moon-for to him may we not ascribe this amiable service ?-deserves more thanks from us terrestrials than we can possibly render. To work the tidegauges of the planet, to fill and empty our harbors, to cover our beaches with magnificent rollers, to clear away the abominations of our polluted rivers, to maintain a regular systole and diastole in the oceanheart, are tasks which that renowned individual executes with exemplary patience and precision. Yonder, in the great silent sea which hides the mysteries of the South Pole, the water begins to heave under his sinewy pull. If the sun should be in conjunction or opposition, he too, though with inferior force, joins in the billowy game. A broad wave is formed, which rushes, or seems to rush, to the north, for the particles have no progressive motion, but simply leap upwards, as if in a vain struggle to reach the moon. Following the course of that wave into the Indian Ocean, you would find that, in about twenty-two hours from the time it appeared at the southern extremity of New-Zealand, it was riding in the Delta of the Ganges, and penetrating into the rivers of Hindostan. Meanwhile, another branch of the great billow makes for the African coast, and rolls into the Atlantic after doubling the Cape of Many Storms. In three hours from the time of its entrance into the noble basin, it sweeps in subdued grandeur past the little "volcanic cinder," Napoleon's rocky prison, where it attains a hight of about two or three feet only. In three hours more it crosses the Line, and, after a further voyage of ten, it flows into the mouth of the English Channel, and prepares to wash the feet of the Ruler of the Waves. Most lovingly does that broad undulation twine round the home

gathered in the streets running at right-angles "As the hour of flood-tide approached, crowds with the Tsien-Tsang, but at safe distances. My position was a terrace in front of the Triwave Temple, which afforded a good view of the entire scene. On a sudden all traffic in the thronged mart was suspended; porters cleared the front street of every description of merchandise; boatmen ceased loading and unloading stream, so that a few moments sufficed to give their vessels, and put out into the middle of the a deserted appearance to the busiest part of one of the busiest cities of Asia. The center of the river teemed with craft, from small boats

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to huge barges, including the gay 'flower boats.' British ship, Little Belt, which was disLoud shouting from the fleet announced the masted off Nova Scotia in 1809, found its appearance of the flood, which seemed like a way into the Basque Roads after a sail of glistening white cable stretched athwart the eighteen months. Two Indian corpses river at his mouth, as far down as the eye could which made their appearance at the reach. Its noise, compared by Chinese poets to that of thunder, speedily drowned that of Azores in the fifteenth century, hinted at the boatmen; and as it advanced with prodi- a strange land beyond the flood; and from gious velocity-at the rate, I should judge, of this dead man's voyage Columbus drew twenty-five miles an hour-it assumed the decided auguries in favor of the unvailed appearance of an alabaster wall, or rather of a world in the west. But in tracing curcataract four or five miles across, and about rents we can not always calculate upon thirty feet high, moving bodily onward. Soon it reached the advanced guard of the immense drifting bodies, nor can we afford to disassemblage of vessels awaiting its approach. mast vessels for the purpose, any more Knowing that the bore of the Hooghly, which than the Chinese would have found it scarcely deserved mention in connection with the prudent to burn a house every time they one before me, invariably overturned boats which wished to indulge in the luxury of roastwere not skillfully managed, I could not but pig. A cheaper expedient may be adoptfeel apprehension for the lives of the floating ed. Throw overboard a bottle containing multitude. As a foaming wall of water dashed a scroll on which is recorded the date and impetuously onward they were silenced, all being intently occupied in keeping their prows whereabouts of your vessel. If this simtowards the wave which threatened to sub-ple little exploring apparatus should fall merge every thing afloat; but they all vaulted, as it were, to the summit with perfect safety. The spectacle was of greatest interest when the cagre had passed about one half way among the craft. On one side they were quietly reposing on the surface of the unruffled stream, while those on the nether portion were pitching and hearing in tumultuous confusion on the flood; others were scaling, with the agility of salmon, the formidable cascade. This grand and exciting scene was but of a moment's duration; it passed up the river in an instant, but from this point with gradually diminishing force, size, and velocity, until it ceased to be perceptible, which Chinese accounts represent to be eighty miles distant from the city."

But if the tidal wave on the high seas is a kind of optical hoax, so far as the actual translation of the waters is concerned, there are great ocean rivers which constantly convey the fluid of one hemisphere to another, and from the cold poles to the glowing Line. Nothing can be more surprising than to reflect that the liquid expanses of our globe are traversed by streams which flow as regularly as the Amazon or Mississippi on land. Channels have been dug out for them apparently, and for thousands of miles they pursue their course between walls of water as if they were treading rocky passes or rolling over granite beds. Some currents are simply periodical, others are variable; but the most important ones are constant, and, if followed, will conduct the navigator along the same settled route as surely as the Rhine will carry a tourist past Bonn and Cologne who starts from Coblentz on his return to the sea. The bowsprit of a

into intelligent hands, it will serve the object as effectually as a broken-down seventy-four. Let it be flung into the sea off the coast of Africa, for example, and if picked up at Jamaica, or found quietly coming to anchor in some English harbor, it will tell its own tale almost as forcibly as if it had kept a regular log. Admiral Beechy has published a chart containing the results of more than a hundred bottle-voyages, and from his interesting document it would appear that some of these fragile mariners had made the circuit of the Atlantic, and then, like Tony Lumpkin's victims, had resumed their route in the vast "circumbendibus." Much, indeed, yet remains to be done in the mapping out of these great ocean streams; but the course of many has been ascertained with sufficient certainty to entitle us to regard them as fixed and well-established highways across the deep.

By far the most influential of these currents is the famous Gulf Stream. Little as it may be appreciated by Englishmen in general, every inhabitant of this country has a greater interest in its flow than he has in the Thames or Tyne. It takes its rise in the Gulf of Mexico, though it may be regarded as a continuation of the mighty equatorial current which sets out from the western coast of Africa, and, after a run of four thousand miles, enters the Caribbean Sea. Sucking up the sun's rays as it advances, and storing away the warmth for future use, it passes into that magnificent indentation in the Mexican coast which

To this stream there is a striking counterpart, so far as it extends, on the corresponding shores of the Pacific. Part of the great equatorial current, after sweeping across that ocean, presses into the seas of China and Japan, where it is deflected like the sister river on the east of the American continent. Thus repelled, it glides over to the opposite coast, and bathes it with its heated wave. Though somewhat indistinctly defined, there can be no doubt that such is the fact, for Asiatic driftwood has been found on the Aleutian isles, and crippled Japanese junks, as was the case with one in 1831, have been borne along to the mouth of the river Columbia. Now, has England no interest in this remote river of the deep? On the contrary, one of her largest provinces is in a great measure dependent upon it for its thermal welfare. As if Providence had expressly adjusted these marine streams for the benefit of our Empire, we find that the recently-established colony of British Columbia is provided with a hot-water apparatus which insures it a much more generous climate than its geographical position would warrant. The temperature of this new state is almost identical with our own. In Great Britain we flatter ourselves that we grow one of the finest races on the

which overlies its route. Imagine the change which would be experienced by Sir Philip Brooke when the air happened to be at the freezing-point on each side, whilst the current itself was nearly fifty degrees in excess! It is obvious that this incessant transport of caloric to the north must have its effect upon our chilly climes. Even where the heated waters can not pass, the winds which sweep over the sea from the south-west must be warmed by contact with the broad diffusive stream. Maury asserts that the surplus heat brought into the region of Newfoundland each day would be sufficient, were it suddenly let loose, "to make the column of superincumbent atmosphere hotter than melted iron." Or, putting the question on a larger basis, he says: "A simple calculation will show that the quantity of heat discharged over the Atlantic from the waters of the Gulf Stream in a winter's day would be sufficient to raise the whole column of atmosphere that rests upon France and the British Islands from the freezing-point to summer-heat." Could any thing be more palpable than the advantages of such a glowing river? If caloric could be stored up in casks, and whole fleets employed in conveying them from the tropics to the northern shores of Europe, some address-globe, and to our gentle skies-neither ed to Britain, some to Norway, some to Spitzbergen, the marks of benevolent design could not be more vividly expressed. In point of latitude England corresponds with Labrador. But we know that the latter region is one where the climate is exceedingly harsh, where the winter is painfully protracted, where the vegetation is feeble and haggard, where the animals are heavily furred to keep them warm, and where the inhabitants are low-typed and extremely unlikely to figure brilliantly in the history of the world. Had we been left in the same lurch, and compelled to subsist on our geographical allowance of caloric alone, England would have been a frost-bitten realm, where fairs might have been held on the Thames every winter, and where boys might have snowballed each other for half the year. Stop the Gulf Stream to-morrow, divert it in some other direction, so that its summer-laden waters should never approach the European shores-and then John Bull would soon become a national pauper; and that oft-anticipated catastrophe, the ruin of the Constitution, would assuredly ensue.

too hot nor too cold, neither enervating our frames by the excessive heat of the south, nor limiting our exertions and crippling our commerce by the frosts of the north-we ascribe, and justly ascribe, the practical superiority of our human ware. Is it not a remarkable circumstance, therefore, that this promising province, with its gold, its coal, and its other splendid mineral endowments-a province which may become the seat of an empire reared by British brawn and animated by British brain-should owe its climatic advantages to a silent river of heat which comes from afar, and discharges its stores of caloric upon the region, as if to protect it from the blighting tyranny of frost?

One great object of currents therefore is plain. It is their duty to equalize as far as may be the climates of the globe, and moderate the extremes of heat and cold. Were not some such precaution adopted, the gathering ice of the poles would ultimately render a large portion of the globe intolerable from excessive frost, whilst the concentrated heat of the tropics might convert them into sultry wastes, some

thing like the burning belt with which old | mocks or icebergs, with waves whose geographers were accustomed to girdle temperature was as high as 36°, though But whilst the equatorial calo- the latitude was upwards of 82°, and though a wilderness of snow lay to the south?

the earth. ric, as we have seen, is incessantly conveyed towards the Polar latitudes, so the Polar cold is incessantly transported toThere is one circumstance, too, which wards the warmer zones of the ocean. gives these marine rivers a peculiar value. The great Antarctic current which flows Water is a bad conductor of heat. If it up the Pacific, skirting the shores of Peru, were requisite to convey the heat of the is estimated at 3500 miles in breadth, and equator to the poles by means of landwas found by Dupetit Thouars to reach streams, the waste of caloric by absorption to a depth of nearly one mile. What a would be considerable, and the object volume of chilled water is this to abstract proposed-namely, the due distribution of from the southern sea and pour into hot-temperature - might be defeated. But ter latitudes! But this beneficent ser- the ocean affords pathways along which vice is as beneficently repaid. Speaking of the Indian and Pacific Oceans, Maury observes:

the liquid warmth may pass, not only to a greater distance, but without any serious loss of power, until it reaches the regions where it can be discharged with most effect. A torrent of molten iron would stiffen and grow cool before it had traveled many miles in contact with the air and earth; but these ocean streams glide from continent to continent without squandering their thermal treasures in needless work by the way.

"These teeming waters bear off through their several channels the surplus heat of the tropics, and disperse it among the icebergs of the Antarctic. See the immense equatorial flow to the east of New-Holland. It is bound for the icy barriers of that unknown sea there to temper climates, grow cool, and return again, refreshing men and beast by the way, either as the Humboldt current or the ice-bearing current, In one respect, however, they seem to which enters the Atlantic round Cape Horn, play a rude and unmannerly part in the and changes into warm again as it enters the economy of nature. Between them and Gulf of Guinea. It was owing to this great the hurricanes and tempests which fresouthern flow from the coral regions that Cap-quently plow up the tropical seas and tain Ross was enabled to penetrate so much further south than Captain Wilkes on his voyage to the Antarctic, and it is upon these waters that that sea is to be penetrated, if ever. The North Pacific, except in the narrow passage between Asia and America, is closed to the escape of these warm waters into the Arctic Ocean. The only outlet for them is to the south. They go down towards the Antarctic regions to dispense their heat and get cool, and the cold of the Antarctic, therefore, it may be inferred, is not so bitter as is the extreme cold of the Frozen

Ocean of the north."

carry devastation even into temperate climes, some powerful attraction appears to subsist. It will be readily understood that a broad river of heated liquid like the Gulf Stream must produce extensive disturbances in the atmosphere above its path. The contrast between its temperature and that of the contiguous ocean and superincumbent air is frequently so violent that an elemental riot may well be anticipated before the equilibrium can be temporarily restored. Hence this summerdispensing stream is supposed to be the parent of many a terrible storm. Some of the most furious gales have been known to gallop along its course as if it were a regular race-ground. Nay, tempests arising on the other side of the Atlantic have been observed to leave their African birth

Another current to the south from the West of Africa was crossed by Captain Grant on one occasion when the temperature of the water in the center ranged as high as 63°, whilst that of the ocean on each side was only 30°. This voluminous stream-1600 miles in breath at the time was hurrying away the heat of the tor-place and make direct for the Gulf Stream. rid zone to the Icy Sea, where its ameliorating presence was required. And how can we explain the existence of an open sheet in the Arctic basin, except on the supposition that currents of warm water from the south flow beneath the surface, and well up where Dr. Kane discovered a spacious ocean, unincumbered by hum

This they followed, keeping steadily to its path, curving where it curved, and recrossing the Atlantic, until their rage was expended, and their wings drooped helplessly on the shores of Europe. The current might, indeed, have grooved a furrow for them in the air.

Availing himself of this fact, Lieutenant