  GRAHAM’S MAGAZINE. Vol. XLI. October, 1852. No. 4. Table of Contents Transcriber’s Notes can be found at the end of this eBook. THE PRIDE OF THE PARTERRE. THE FORGOTTEN WORD. DERWENTWATER.[The sad story of the Earl of Derwentwater, executed in 1716 for participation in the rebellion of the previous year, is well known. The beautiful lake from which he derives his title is surrounded by some of the grandest scenery in England. Few persons will need to be reminded of the beauty of the small cataract of Ladore. The memory of the misfortunes of Lord Derwentwater, and of the beauty of his disconsolate countess, is is still preserved in the traditions of the neighbourhood.] Sweet lake of the moun-tains how happy was I, When life’s sunny morn had no cloud on its sky, And I roam’d with my love on thy beautiful shore, To hear the deep music that gush’d from Ladore!
We sail’d on thy waters rejoicing, alone, Or trod thy green islands, and call’d them our own, And built, ’mid the hills that encircle thy breast A bower and a home in the wilds of the West.
But sorrow has darken’d the noon of our day, And peril and doubt have encompass’d our way; My heart’s only love in captivity lies, And thy glory, O Derwent, is dimm’d in mine eyes.
Sad lake of the mountains, through dangers I roam, With a pang in my heart and a blight on my home, To dream of the joys that shall bless me no more, And mingle my sighs with the moan of Ladore. GRAHAM’S MAGAZINE. Vol. XLI. PHILADELPHIA, October, 1852. No. 4. SONNET:—TO THE REDBREAST.When that the fields put on their gay attire, Thou silent sitt’st near brake or river’s brim, Whilst the gay thrush sings loud from covert dim; But when pale Winter lights the social fire, And meads with slime are spent, and ways with mire, Thou charm’st us with thy soft and solemn hymn, From battlement or barn, or hay-stack trim; And now not seldom tun’st, as if for hire. Thy thrilling pipe to me, waiting to catch The pittance due to thy well-warbled song: Sweet bird, sing on! for oft near lonely hatch, Like thee, myself have pleased the rustic throng, And oft for entrance ’neath the peaceful thatch, Paid the cheap tribute of a simple song. ——— BY MRS. TOOGOOD. ——— Unskilled in lore was Fanny Leigh, But learned in wisdom mild, That glowed all soft and tenderly In that meek, blue-eyed child.
And why the sigh? why sad the brow? She conned it o’er and o’er, And found out anxious thoughts, and how They prey upon the poor.
Her soft young hands, she did not fear, Could aid the feeble old: How blest for her to wipe their tear, And clothe them from the cold!
And she hath left the rose-clad cot, From youth’s one home to part, Armed with resolve—revealing not What tempest at her heart.
None saw the drops that dimmed her eye, When a sad breeze and keen Came answering with a long-lorn sigh From that still village scene.
Forth hath she gone—a summer boat Skims o’er the glassy bay With slender strength—nor dreads to float Where the stern waters lay.
Forth hath she gone, from dewy field, And used to fondest care, To try the desert—will it yield One shelter from the glare?
Where Innocence is shamed to quail Before the worldling’s mirth; And beautiful will learn to veil Its scorned, yet heavenly birth.
Forth so she went, yet ’mid the pest, The blast of noxious night; A lamp burned stedfast at her breast, And cast its certain light.
And oft she heard a mellowed tone Streaming above the din; A Voice that loves the pure and lone, And strengthens them within.
O! there was joy, even unto pain, When, passed those days so drear, As music, Fanny’s steps again Fell on each aged one’s ear.
And who, the gladdest of the glad, Stands at the gate? I pray. Is’t he who then a very lad So wept her going away?
’Tis he, who, while he fed his flowers, (Stronger her bright chain grew,) Saw constantly through haunted hours Those eyes of gentlest blue. It has been mentioned as a part of the planetary constitution of our globe, that a gaseous envelope environs its mass, the atmosphere, which requires the attention of the astronomer, on account of its influence in displacing the celestial bodies, and contributing to their visibility, by refracting and reflecting the rays of light. This elastic fluid is the scene of interesting phenomena, and performs important functions in the economy of nature. Besides being essential to the life of man, and the animal races, whose existence would terminate in a few minutes without the respiration of it; the exhalation of moisture from the surface of the earth is mainly owing to the common air we breathe, which receives and sustains the vapors formed into clouds, distributes them over different regions by its incessant motions, and tempers by its currents those extremes of heat and cold to which various localities are subject. It is in these last-named offices that the atmosphere demands the notice of the physical geographer. The consideration of its actual constitution does not belong to his province, but a general view of the fluid may be appropriate before we proceed to those agitations and changes which are in constant action, and upon which the welfare of organized beings so materially depends. The atmosphere is, then, an integral portion of the earth, a body of air revolving with the solid mass upon its axis, the higher strata, of course, increasing in velocity with the distance from the axis of revolution. From hence a conclusion may be drawn respecting its height, for an absolute limit is put to its elevation by this feature of its physical condition. There is a point where the centrifugal force, or the tendency to fly off from the centre, will counterbalance the centripetal, or the gravitation toward the centre, and beyond that point the latter will be vanquished. It is obvious that no portion of the atmosphere can extend beyond the point where the two influences balance, or are in equilibrium, and the projectile force becomes greater than that of gravitation, or its projection into space would follow. At the distance of 6.6 radii from the centre of the earth, or at an elevation of 22,200 miles, about the eleventh part the distance of the moon, this point is fixed, beyond which it is impossible for the atmosphere in the smallest quantity to extend. This consideration is only of importance to show that physical laws rigidly restrict it within finite bounds, for any portion of air at that distance must have a tenuity which is utterly inconceivable. The indications of the height of the atmosphere drawn from its weight, as shown by the barometer, reduce its elevation within a vastly circumscribed limit. A column of the whole circumambient air is nearly equal in weight to a similar column of mercury of thirty inches, or of water of thirty-four feet, which would give it an elevation of but 27,000 feet, or rather under five miles, if its density were uniform. But the elasticity of the air causes it to expand with the diminution of its own pressure, which becomes less at every step from the surface of the earth; and owing to this expansion we must place the limit to its height at a far greater distance than that suggested by the simple barometrical measurement of its weight. A pretty common opinion prevails that its extreme boundary does not exceed forty or fifty miles, and we have sensible evidence on the high lands of the globe, that for all the purposes serviceable to vegetable and animal life, the atmospheric zone is of very contracted elevation. It is a well-known property of the air that the temperature diminishes with its height, a circumstance referable to the general physical law, that as the density of gases decreases they acquire an increased capacity for heat. The higher, therefore, a body ascends in the atmosphere, the greater is the quantity of heat abstracted from it, the surrounding fluid becoming more rare. Hence the perpetual snow, and the piles of glaciers, that crown the summits of mountains, at whose base the orange and the citron bloom, and man pants in the fierce sultriness of a torrid climate. But while the atmosphere may be considered generally as an aerial zone of the earth, the companion of the massy spheroid in its annual revolution round the sun, and rotating with it upon its axis, it has independent movements which present very complex phenomena, however clear the causes which put them in operation. The particles of air are constantly suffering displacement, and it is easy to conceive of various circumstances disturbing the dilatable and elastic fluid in which we live. A body in movement will communicate its motion to the adjoining particles, which may be sensibly propagated by them to a considerable distance; but this cause operates so slightly in the production of atmospheric currents that it might be entirely overlooked. It will be sufficient to state that some of the vast oceanic streams are supposed to produce a corresponding flow in the air. The varying attractions of the sun, moon, and planets on the atmosphere, will occasion tides in it analogous to those of the ocean, or an alteration in the heights of vertical columns of air, winds and currents arising from the resulting inequalities of horizontal pressure; but La Place has proved the action of this cause to be scarcely appreciable. The atmospheric agitations of which we are sensible, both the more violent and gentle, appear to proceed either from a change in the temperature of a portion of the air, or from a change in the quantity of water which it holds in a state of vapor. In both these cases a temporary destruction of the equilibrium subsisting between different parts of the atmosphere is produced, and its particles are set in motion to restore the balance. The effect of heat upon a volume of air is to rarefy and expand, to increase its bulk and diminish its density. When any portion, therefore, of the earth’s surface is more heated than the surrounding districts, the air there ascends and flows over the adjoining cooler and denser strata, causing an upper outward current, while the colder and denser fluid rushes toward the spot where the balance has been lost by expansion, and a lower inward current is produced. An easy experiment will illustrate this interchange. In a room warmed by a good fire, if a candle be held at the crevice between the door and the floor, an inward current will be observed from the exterior colder air, but near the ceiling, by the same means, an outward flow will be detected. In the other condition an addition of vapor to the atmosphere gives rise to a wind blowing on all sides away from the district of evaporation, while an abstraction of it by showers creates a partial vacuum, toward which the air rushes from all points of the compass. The diversity of the winds in power is principally owing to the different degrees of vigor with which these causes act. The currents of the atmosphere display an endless variety in their velocity and force, from the zephyr, which scarcely stirs the leaves of the forest, to the gale under which its mightiest branches bend, and the hurricane which tears up its trees by the roots, and destroys the habitations of mankind. It has been observed that in the temperate zone the most violent winds occur, when neither the heat nor the cold common to such localities are at its maximum—that they generally extend over a considerable tract of country—and are accompanied by sudden and great falls in the mercury of the barometer. The latter circumstance attends the storms of the tropics, but they are often confined within narrower limits than the extra-tropical hurricanes. It was noticed by the superstitious as a coincidence, not without meaning, that at the time of Cromwell’s death the enchained winds were liberated, and went forth raving and howling through the land, uprooting the largest trees, and whirling them about like straws, and toppling down chimneys and turrets; but the same tempest, at the self-same hour, dashed the vessels of the Baltic sea even upon the strand, and buried Venetian argosies in the Adriatic, shivered the pines of Norway, and swept before it the cypresses of the Bosphorus—a similar war of the elements attending the termination of the earthly career of Cardinal Wolsey, Bonaparte, and George IV. Sometimes the upper regions of the atmosphere have been remarkably agitated, while the lower stratum of the air has been quite calm. Lunardi, on one occasion, traveled at the rate of seventy miles an hour in his balloon, while at Edinburgh; when he ascended, the air was quite tranquil, and continued so throughout his expedition. To ascertain the velocity and force of winds, a variety of experiments have been made with instruments constructed for the purpose. The following table contains some results obtained by Smeaton, inserted in a volume of the Philosophical Transactions:— VELOCITY OF THE WIND.
The currents of the atmosphere far surpass in velocity those of the rivers and the ocean, a gentle pleasant wind blowing at a rate equal to that of the mighty Father of Waters when in flood, but a hurricane will outstrip the swiftest locomotive in its speed. In speaking of the direction of currents of air and water, the indicating terms are employed in an inverse sense, an easterly wind signifying a breeze coming from that quarter, an easterly stream a flow of water toward it. Winds may be divided into three classes or genera, the Permanent, the Periodical, and the Variable; of which, the first excepted, there are many different species. We shall prefer, however, to consider them under their local recognized titles. A Calm at Sea. 1. Trade winds. These are permanent, following the same direction throughout the year. They are met with between the tropics, and a few degrees to the north and south of those limits. The well-known name applied to them is a phrase of doubtful origin, but probably derived from the facilities afforded to trade and commerce by their constant prevalence and generally uniform course, though Hakluyt speaks of the “wind blowing trade,” meaning a regular tread or track. The parallels of 28° north and south latitude mark the medium external limits of the trade winds, between which, with some variations, their direction is from the north-east, north of the equator, and from the south-east, on the other side of the line, hence called the north-east and south-east trades. They are separated from each other by the region of calms, in which a thick foggy air prevails, with frequent sudden and transient rains attended by thunder and lightning. This region, in the Atlantic, extends across the whole ocean from the coasts of Africa to those of America, but its position shifts, being sometimes entirely north of the equator, and but rarely reaching one or two degrees south; and hence it may be considered as belonging to the northern hemisphere. The region also varies in breadth from two and a half to ten degrees, but usually occupies a width of four or five. These variations are dependent upon the position of the sun, which has an influence likewise upon the strength, direction, and situation of the trade winds themselves. When the sun has a northern declination, and approaches the tropic of Cancer, the boundary line of the north-east trade wind extends to 32° north latitude, and the wind has a more easterly direction, but the parallel of 25° is its northern boundary, and the wind inclines more north when the sun is south of the equator, and approaches the tropic of Capricorn. At that season, the southern boundary of the south-east trade wind extends to 30° S. lat., and the whole ocean is swept by it between that line and about 1° N. lat. The general width of the south-east trade is about 9° greater than that of the north-east, the region of calms, as before stated, being almost wholly in the northern hemisphere. In the basin of the Atlantic, the zone of the trade winds becomes broader, and their direction more easterly, as the coast of America is approached, the breezes blowing to the very shore. This is not the case on the African side of the Atlantic, where, through a tract of sea extending from fifty to eighty miles off shore, these winds are not found at all, but contrary westerly breezes prevail. The irregularity is easily explained. Owing to the rarefaction which the air undergoes over the great hot desert of the Sahara, the colder air from the contiguous sea rushes in to supply the partial vacuum created, and keep up the equilibrium of the atmosphere, producing winds blowing toward the shore. In the Pacific Ocean, a similar zone is occupied by permanent north and south-easterly breezes, or trade winds, though subject to a variety of interruptions. An instance of irregularity occurs along the coasts of Peru and Chili, where the general direction of the wind is south, and a steady south-easterly wind is only experienced at the distance of five or six hundred miles from the shore. The numerous shoals and islands which are found in the Pacific, prevent uniformity in the tropical movements of the atmosphere. That intelligent hydrographer Captain Horsburgh has observed, that where shoal coral banks shoot up out of the deep water in many places between the tropics, a decrease of the prevailing wind is frequently experienced; for when a steady wind is blowing over the surface of the deep water, no sooner does a ship get upon the verge of a shoal coral bank, than a sudden decrease of the wind is often perceived. This he supposes to be occasioned by the atmosphere over these banks being less rarefied by the increased evaporation than that over the deep water, and consequently not requiring so great a supply of air to restore the equilibrium as the circumjacent parts, which are more rarefied and heated. It would undoubtedly be the case, if the earth were entirely covered with a mantle of water of uniform depth, that the trade-winds would everywhere prevail, throughout a zone, bounded by the parallels of from 25° to 32° on each side of the equator. But the large masses of land, of uneven surface, which occur between the tropics, and the consequent inequalities of temperature, check the tendency of the intertropical atmosphere to a regular course, introduce derangement in its movements, so that it is only in the great open seas that the trade-winds are experienced. Still, it has been observed that, in some countries under and near the equator, constant easterly winds are found, which are no doubt identical in their cause with those that distinguish the equatorial regions of the ocean. They are met with on lands which exhibit extensive level plains, where nothing occurs to obstruct their passage and alter their direction. Thus, along the immense low tract drained by the Amazon an easterly wind prevails, by the assistance of which, the voyager is enabled to ascend rapidly against the strong current of the river. This wind blows from the estuary of the Amazon, where it is moderate, to its sources at the foot of the Andes, where it has gathered such strength, that Humboldt found it difficult to make head against it. The plain traversed by the lower course of the Orinoco has a similar easterly breeze, but of less force. We owe the discovery of the trade winds to Columbus, and this would have been prominently connected with his name, had it not been supplanted by the glory of a greater achievement, the revelation of a new world to the knowledge of mankind. The ancients were entirely unacquainted with these permanent breezes, and though maritime adventure had been largely prosecuted by the Portuguese at the instigation of Prince Henry, they had not penetrated into the region of the trades. Proceeding cautiously along the shores of Barbary, they had explored the coasts of Africa to Cape de Verde, rescued the Azore Islands from the “oblivious empire of the ocean,” and afterward, under Vasco di Gama, doubled the Cape of Good Hope; but these voyages carried them clear of the district of the north and south-east trade winds. But soon after leaving the Canaries in the Santa Maria, Columbus fell in with the former, which in the summer extend to the latitude of those islands, and—for the first time—a sail from the Old World swelled before the steady breath of the northern tropic. This circumstance, favorable to the success of his expedition, speedily excited the apprehensions of his crew, who found themselves borne, day after day, by a permanent breeze, farther from their native shores, and inferred the impossibility of returning, as they observed no change in its direction. Fortunately for his fame, and for the world, the great navigator firmly held on his course, reached the bounds of the before-supposed illimitable ocean, and re-crossed it in the region of the variables, to the north of the northern trade wind. Now, in passing from the Canaries to Cumana, on the north coast of South America, it is scarcely ever necessary to touch the sails of a ship; and with equal facility the passage is made across the Pacific, from Acapulco, on the west coast of Mexico, to the Philippine Islands. If a channel were cut through the Isthmus of Panama, the voyage to China would be remarkably facilitated by the trade winds of the Atlantic and Pacific Oceans; be more speedy, agreeable, and safe than the usual route by the Cape, the chief interruption to its uniformity occurring in the Caribbean Sea and the Gulf of Mexico, where the trade wind blows impetuously, the sea is stormy, and the sky gray and cloudy. The theory respecting the origin of the trade winds, adopted by Doctor Dalton, Professor Daniell, and Sir John Herschel, was first proposed by George Hadley, the brother of the inventor of the quadrant, and embodies features of the previous theories of Halley and Galileo, who both grappled with this great geographical phenomenon. It is founded upon the rarefaction of the atmosphere of the torrid zone by the powerful heat to which that region is subject, in connection with the different velocities of the earth’s surface, in different degrees of latitude, in the diurnal rotation. Heat rarefies and expands a volume of air in a ratio equivalent to an addition of about seventy feet to the ordinary height of the atmosphere for every degree of thermometrical measurement. As the sun is always vertical at some place within the tropics, the average temperature of the earth’s surface in that region, bounded by the parallels of 23½° on each side of the equator, is much higher than in latitudes to the north and south; and the incumbent air acquiring this higher temperature, is thereby rarefied and expanded. The consequence is, that in obedience to hydrostatical laws, masses of air are continually buoyed up from the surface, or swelled round the torrid zone in the form of a protuberant belt, the upper strata flowing over, and running off in streams north and south toward the poles, where—having been cooled and condensed—they descend, and flow over the surface toward the equator, pouring in a perpetual current of air to supply the place of that buoyed up by the heat of the tropics. Thus, there is a constant current in the higher regions of the atmosphere, proceeding from the equator northward and southward to the poles; and, if the earth were at rest, there would be a constant wind in the lower regions of the atmosphere blowing directly from the poles to the equator, while in equatorial regions the two streamlets would meet, and neutralize each other’s influence. But the earth is not at rest! It is incessantly whirling upon its axis, the surface moving at a rate which varies according to the extent of the circumference. The velocity at the equator, where the circumference is the greatest, is about sixteen miles a minute; at 30° of latitude, which is below the most southerly point of Europe, it is about fourteen miles in the same time; and at 45°, or about the centre of France, it is about eleven miles. As the distance from the equator increases, north and south, the rate of the rotation thus becomes less, because the circle of the earth’s circumference diminishes in extent. Now a current of air flowing from the north or south polar regions, and setting toward the equator, will encounter as it proceeds an increased rotatory motion eastward, the direction of the earth’s axical revolution; and, not acquiring the new velocity at once, it will be left behind, and seem to deflect toward the west just in proportion as it does not keep up with the earth to the east. Hence, what would simply be a north or south wind but for the earth’s rotatory motion, becomes a north-east and south-east wind as it approaches those regions where, the velocity of the globe being so much greater than where it originated, it lags behind it in its easterly course. This is the exact path of the trade winds—breezes, with few exceptions, uniform in their direction, perpetual in their motion, and steady in their force—which wafted Columbus across the Atlantic, impelled the Portuguese from their southerly course, and bore them to the Brazils, and have since been important auxiliaries to the communication of the eastern with the western continent. The existence of a current in the upper regions of the atmosphere counter to that below, assumed by the preceding theory, is not mere hypothesis. Clouds, though of rare occurrence in the district of the trade winds, have been observed to take a direction contrary to that which the surface-breezes would have given them. A circumstance remarkably in favor of the counter-current inferred from theory, occurred in the year 1812. There was then an eruption of the volcano of St. Vincent, one of the West India Islands, which covered the island of Barbadoes with a quantity of the ashes and volcanic matter ejected. The trade wind here blows with great power, and it is certain that the volcanic ashes would have been conveyed in a direction from Barbadoes, instead of toward it, by its action. To account for their transportation thither, it is necessary to suppose that the volcano ejected them to an elevation within reach of a superior stratum of air, blowing contrary to the course of the inferior current. When Humboldt was upon the Peak of Teneriffe the west wind blew with such violence that he could scarcely stand, though the island below was under the influence of the ordinary north-east trade wind; and the remark has often been made, that in the elevated parts of the Canary Islands, a contrary wind has been experienced to that which has been prevailing over the general surface. All mariners and passengers have spoken with delight of the region of the trade winds, not only on account of the favoring gale, but its genial influence, the transparent atmosphere, the splendid sunsets, and the brilliancy of the unclouded heavens, day and night. Columbus, in recording his first voyage into their territory, compares the air, soft and refreshing without being cool, to that of the pure and balmy April mornings he had experienced in Andalusia, wanting but the song of the nightingale and the sight of the groves, to complete the fancy that he was sailing along the Guadalquivir, “It is marvelous,” observes Las Casas, “the suavity which we experience when half way toward these Indies; and the more the ships approach the lands so much more do they perceive the temperance and softness of the air, the clearness of the sky, and the amenity and fragrance sent forth from the groves and forests; much more certainly than in April in Andalusia.” Humboldt lingers with pleasure, upon his first acquaintance with the tropical regions at sea, upon the mildness of the climate and the beauty of the southern sky, gradually opening new constellations to the view, stars contemplated from infancy progressively sinking and finally disappearing below the horizon, an unknown firmament unfolding its aspect, and scattered nebulÆ rivaling in splendor the milky way. “A traveler,” he states, “has no need of being a botanist, to recognize the torrid zone, on the mere aspect of its vegetation; and without having acquired any notions of astronomy, without any acquaintance with the celestial charts of Flamstead and De la Caille, he feels he is not in Europe, when he sees the immense constellation of the Ship, or the phosphorescent clouds of Magellan, arise on the horizon. We pass those latitudes, as if we were descending a river, and we might deem it no hazardous undertaking, if we made the voyage in an open boat.” Mr. Bailey, in his Four Years in the West Indies, relates an adventure, nearly answering to that here referred to. The master of one of the small fishing smacks that ply along the coast of Scotland, who had no other knowledge of navigation than that which enabled him to keep his dead reckoning, and to take the sun with his quadrant at noon-day, having heard that sugar was a very profitable cargo, determined, by way of speculation, upon a trip to St. Vincent, to bring a few hogsheads of the commodity on his own account into the Scottish market. Accordingly, he freighted his vessel; made sail; crossed the Bay of Biscay in a gale; got into the trade winds, and scudded before them, at the rate of seven knots an hour, trusting to his dead reckoning all the way. He spoke no vessel during the whole voyage; and never once saw land until on the morning of the thirty-fifth day, when he descried St. Vincent’s right ahead, and running down, under a light breeze, along the windward coast of the island, came to anchor. The private signal of the little vessel was unknown to any of the merchants, and it immediately attracted notice. The natives were perfectly astonished—they had never heard of such a feat before; and deemed it quite impossible that a mere fishing smack, worked only by four men, and commanded by an ignorant master, should plow the billows of the Atlantic, and reach the West Indies in safety—yet so it was. This relation justifies the title given by the Spaniards to the zone where the trade winds are constant, el Golpo de las Damas, the Sea of the Ladies, on account of the ease with which it may be navigated, the uniform temperature prevalent night and day, and its pacific aspect. Commencement of the Monsoon. 2. Monsoons. These are periodical winds, which sweep the northern part of the Indian Ocean, changing their direction after an interval of about six months, and hence the term Monsoon, the Anglicised form of the Persic mousum, or the Malay moossin, signifying a season, referring to their periodicity. Avoiding all minute detail, we shall merely give the range, direction, and duration of these singular, yet highly useful currents, and that in a very general way. From 3° south of the equator to the northern shores of the Indian Ocean, including the Arabian Sea, the Bay of Bengal, and the Chinese Sea, a south-west wind blows from April to October, and then a north-east wind sets in, and prevails through the next half year, from October to April. From 3° to 10° south of the equator a south-east wind blows from April to October, and a north-west during the succeeding six months. Without attending to local variations, these are the general phenomena. There is a south-west wind prevailing north of the equator from April to October, and southward of this, through a certain space, at the same season, a south-east wind. There is a north-east wind north of the equator from October to April, and coincidently, a north-west wind between 3° and 10° south of the line. The western boundary of the region of the monsoons is the African shore; its eastern limit is supposed to be about the meridian of 136° east longitude, which cuts the island of New Guinea; its northern confine is near the parallel of 27° north latitude, which intersects the Loo Choo islands; its southern extremity has been already stated. The monsoons are much stronger than the trade winds, and may be called gales, but they are by no means of uniform force, either as it respects themselves or each other, the same monsoon occasionally blowing with such violence that ships are obliged to reef their sails. It must not be imagined that these winds are confined to the ocean. They extend over the whole of HindÛstan to the Himalaya, the north-east monsoon bringing copious rains to its eastern shores, and the south-west monsoon performing the same office for its western coast. The change of the monsoon—the periodical shifting of the wind—the most singular feature of the case, is a gradual process, usually occupying about a month, which reduces the reign of the two annual monsoons, north and south of the equator, to five months each, the remaining two months being spent in the transitions. In each interval of change, calms, light variable breezes, alternate with storms of tremendous violence. Mr. Caunter thus describes the scene at Madras, in the interim between the cessation of one monsoon and the setting in of another: “On the 15th of October, the flag-staff was struck, as a signal for all vessels to leave the roads, lest they should be overtaken by the monsoon. On that very morning some premonitory symptoms of the approaching “war of elements” had appeared. As the house we occupied overlooked the beach, we could behold the setting in of the monsoon in all its grand and terrific sublimity. The wind, with a force which nothing could resist, bent the tufted heads of the tall, slim cocoa-nut trees almost to the earth, flinging the light sand into the air in eddying vortices, until the rain had either so increased its gravity, or beaten it into a mass, as to prevent the wind from raising it. The pale lightning streamed from the clouds in broad sheets of flame, which appeared to encircle the heavens as if every element had been converted into fire, and the world was on the eve of a general conflagration, whilst the peal, which instantly followed, was like the explosion of a gunpowder magazine. The heavens seemed to be one vast reservoir of flame, which was propelled from its voluminous bed by some invisible but omnipotent agency, and threatened to fling its fiery ruin upon every thing around. In some parts, however, of the pitchy vapor by which the skies were by this time completely overspread, the lightning was seen only occasionally to glimmer in faint streaks of light, as if struggling, but unable, to escape from its prison, igniting, but too weak to burst, the impervious bosoms of those capacious magazines in which it was at once engendered and pent up. So heavy and continuous was the rain, that scarcely any thing, save those vivid bursts of light which nothing could arrest or resist, was perceptible through it. The thunder was so painfully loud, that it frequently caused the ear to throb; it seemed as if mines were momentarily springing in the heavens, and I could almost fancy that one of the sublimest fictions of heathen fable was realized at this moment before me, and that I was hearing an assault of the Titans. The surf was raised by the wind and scattered in thin billows of foam over the esplanade, which was completely powdered with the white, feathery spray. It extended several hundred yards from the beach; fish, upward of three inches long, were found upon the flat roofs of houses in the town, during the prevalence of the monsoon, either blown from the sea by the violence of the gales, or taken up in the water-spouts, which are very prevalent in this tempestuous season. When these burst, whatever they contain is frequently borne by the sweeping blast to a considerable distance over-land, and deposited in the most uncongenial situations; so that now, during the violence of these tropical storms, fish are found alive on the tops of houses; nor is this any longer a matter of surprise to the established resident in India, who sees every year a repetition of this singular phenomenon. During the extreme violence of the storm, the heat was occasionally almost beyond endurance, particularly after the first day or two, when the wind would at intervals entirely subside, so that not a breath of air could be felt, and the punka afforded but a partial relief to that distressing sensation which is caused by the oppressive stillness of the air so well known in India.” It is an extraordinary but well-ascertained fact, that as soon as one monsoon ceases, though a month may elapse before the succeeding one appears, the clouds take the direction of the approaching monsoon, and thus from the regions of the atmosphere herald its advent to the dwellers below. We naturally inquire concerning the origin of these peculiar movements, but must be content with a very scanty measure of information upon the subject. The laws which nature obeys in these periodical changes are undoubtedly identical with those which give rise to atmospheric currents in general, but their mode of operation is in this case obscure. The north-east and south-east monsoons, the former on the north and the latter on the south side of the equator, may be considered as trade winds, explicable upon the same principles, but counteracted for a certain time by causes which produce winds from a different quarter, the south-west and north-west monsoons. It has been observed that the south-west monsoon, which prevails to the north of the equator, is coincident with the sun being vertical to that region, when HindÛstan, Siam, and the adjacent countries receive their maximum of heat. Consequently, the incumbent air, being rarefied, ascends, and a rush of colder air to supply its place, is produced from the southward, which is then receiving the oblique rays of the sun, and which presenting a surface of water is immensely less heated than the lands to which the luminary is perpendicular. In like manner, the north-west monsoon, which prevails south of the equator, is coincident with the sun being south of it likewise, and vertical to the region, when the sandy plains of New Holland become powerfully heated, and the air over them rarefied, creating a wind by the rush of the colder northern air toward the point of rarefaction. These are the explanations commonly given, and though in several respects they do not account for all the phenomena, yet the probability is, that they present the correct theory, anomalous circumstances arising from the influence of causes which are local and as yet unknown. The monsoons are more valuable as auxiliaries to commerce than the trade winds, owing to the change in their direction, for a ship may proceed to a distant port with one monsoon and be aided on its return by its successor. 3. Land and sea breezes. A line in one of our popular songs, |
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