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pool are extended in a circle about thirteen miles in circumference. In the midst of this stands a rock, against which the tide in its ebb is dashed with great fury. It swallows
ир all things that come within the sphere of its violence,-trees, timber, and shipping. No skill in the mariner, nor strength of rowing, can work an escape. The sailor at the helm finds the ship at first go into a current opposite to his intentions. His vessel's motion, though slow in the beginning, becomes every moment more rapid ; it goes round in circles still narrower and narrower, till at last it is dashed against the rocks, and instantly disappears; nor is it seen again for six hours, till the tidc flowing, it is vomited forth with the same violence with which it was drawn in. The noise of this dreadful vortex still farther contributes to increase its terror, which, with the dashing of the waters, and the dreadful valley, if
may be so called, caused by their circulation, makes one of the most tremendous objects in nature. It is only, however, at certain seasons, when a flood-tide setting in from the south-west, meets with a strong gale producing a current in a contrary direction, that this whirlpool assumes so formidable an appearance; and hence those navigators who have visited the Malström in a calmer season, allege that its terrors have been greatly exaggerated.
It is now ascertained, that the whirlpool of Charybdis, in the straits of Messina, and that of Euripus, near the island of Euboea, do not possess the terrors attributed to them by the ancients.
WHEN river-courses lie amongst mountains, they are subject to sudden breaks, which, according to their depth, give rise either to rapids or to cataracts. There are many picturesque waterfalls in Scotland, as the cascade of Fyers, and that at Lochleven-head in Inverness-shire, Bruar cascade in Athol, the Devon lynn in Clackmannanshire, and the magnificent falls of the Clyde, near Lanark. The most stupendous cascade in Great Britain, is the Fall of Glomach, in the district of Applecross, in the parish of Kintail, and county of Ross. At the head of a wild and solitary glen, seven miles from the inn of Shealhouse, the river Girsac is precipitated in one unbroken fall of more than three hundred feet. At the distance of about fifty feet from the bottom, the water impinges on a shelf, whence it falls into a dark pool amidst naked perpendicular rocks. When the river is in flood, it descends in one unbroken sheet of above 380 feet in height. Cumberland has one or two beautiful cascades on a smaller scale; and Wales has several, particularly the Pistil y Cain, and Pistil y Mouddach, in Merionethshire. The cataracts of the Glommen in Norway, of the Dahl in Sweden, of the Staubach in the Alps, of Tivoli and Terni in Italy, the far-famed Styx in Arcadia, and the Fall of the Rhine at Schauffhausen, are amongst the most celebrated in Europe.
The famous cataract of Tequendama near Bogota, though found by Humboldt to be far less lofty than had been supposed by Bouguer, is still of stupendous height, and one of the most magnificent in the world ; a river half the breadth of the Seine at Paris is precipitated into a rocky gulf, at two bounds, to a depth of 540 feet. This fall is in one of the wildest scenes in the Cordilleras, surrounded by lofty mountains, and the two leaps are down a nearly perpendicular rock. This overwhelming body of water, when it first parts from its bed, forms a broad irch of a glassy appearance; a little lower down it assumes a fleecy form ; and ultimately in its progress downwards, shoots forth into millions of tubular shapes, which chase each other more like sky-rockets than any thing else they can be compared to. The changes are as singularly beautiful as they are varied, owing to the difference of gravitation, and the rapid evaporation which takes place before reaching the bottom. The noise with which this immense body of water falls, is quite astounding; and the dense clouds of vapour, which rise to a considerable height, and mingle with the atmosphere, form in their ascent the most beautiful rainbows. The most conclusive proof of the extraordinary evaporation, is the comparatively small stream which runs off from
the foot of the fall; it rushes, however, impetuously along its stony bed, overhung with trees, and loses itself in a dark winding of the rock. The column of vapour, rising like a thick cloud, is seen from the walls round Bogota at fifteen miles distance.
A cataract may exist in a comparatively flat country, from a sudden sinking in its level. The stupendous cataract of Niagara, in which a large and rapid river, 1650 feet in width, precipitates itself, in one vast leap of 160 feet perpendicular, is an instance of such an oecur
This amazing fall of water is made by the river St Lawrence, in its passage from the lake Erie into the lake Ontario. The cataract is not in a straight line across, but, hollowing inwards like a horse-shoe, presents a kind of theatre, the most tremendous in nature. Just in the middle of this circular wall of waters, a little island, that has braved the fury of the current, presents one of its points, and divides the stream at top into two, but it unites again long before it has got to the bottom. The noise of the fall is heard at the distance of several leagues ; and the fury of the waters, at the bottom of their fall, is inconceivable. The dashing produces a mist that rises to the very clouds, and that produces a most beautiful rainbow when the sun shines.
But the cataract of the river Shirawati, in the Indian province of Canara, exceeds in beauty and sublimity every waterfall which has been hitherto made known to
The country around the village of Haliali, about three miles north-west of the fall, presents the richness of a tropical forest, mingled with cultivation. The traveller comes suddenly on the river. A few steps over huge blocks of granite bring him to the brink of a fearful chasm, rocky, bare, and black, down into which he looks to the depth of a thousand feet. The bed of the river is one-fourth of a mile broad, in a direct line; but the edge of the fall is elliptical, with a sweep of about half a mile. This body of water rushes at first for about three hundred feet over a slope at an angle of 45° in a sheet of foam, and is then precipitated to the depth of eight hundred and fifty feet more into a black abyss, with a thundering noise. It has therefore a depth of 1150 feet. In the
rainy season the river appears to be about thirty feet in depth at the fall ; in the dry season it is much lower, and is then divided into three cascades of varied beauty and astonishing grandeur ; but the smaller streams are almost dissipated in vapour before they reach the bottom.
XII.-OVERFLOWINGS OF RIVERS.
The periodical inundations of rivers depend on great falls of rain in mountainous regions, or on the melting of snows in the neighbourhood of their source. The period depends on the return of these seasons in different places. Within the tropics the rainy season is usually about the time when the sun passes the latitude of the place towards the tropic; and continues until his return to the same point. The floods of the Maranon and La Plata cover a vast extent of unexplored country. The rise of the Orinoco commences in May, its inundation begins in June, and the waters return to their channel in September; from which time they decrease until April of the succeeding year. In the inundations of the Mississippi, the waters at their height, 1000 miles from the sea, attain a rise of fifty feet; at 300 miles from the sea they rise twenty-five feet; and at 100 miles only twelve feet. The western bank of the Mississippi forms a vast series of lakes, which are dried up in autumn into arid plains, interspersed with swamps; but the delta below the junction of Red River, is a dismal swamp, scarcely elevated above the sea. In the Red River, the Arkansas, and the Lower Mississippi, are found those enormous rafts of drift-wood, formed during the riverfloods, which sometimes extend for ten or twelve miles in one mass, rise and fall with the stream, yet have a luxuriant vegetation on their summits. In the inundations of the Ganges, the waters begin to increase in April, and are at their height in July, when the country, for one hundred miles along its banks, presents the appearance of a vast lake, interspersed with insulated villages and woods. The general height of the inundationwaters in Bengal, is about twelve feet, but in some places they have a depth of more than thirty feet. The great river of Ava, the Indus, the Euphrates, and the Tigris, have also their periods of inundation, depending on the circumstances which determine the setting in of the rains on the mountains in which they originate.
The inundations of the Nile have long been celebrated. Shortly after the commencement of the rains in the mountains of Abyssinia, in June, the river begins to rise, and attains its greatest height in August, when the valley of Egypt, with a mean breadth of ten or twelve miles, and the greatest part of the delta, are covered with one sheet of water. At Cairo, the greatest rise is twentyeight feet, but at Rosetta it is not more than four. As soon as the waters are within their usual channel, the soil, moistened and enriched by the sediment deposited from the inundation, is diligently cultivated by the natives.
The river Senegal has likewise its inundations, which cover the whole flat country of Negroland, beginning and ending much about the same time as the Nile. But the difference between the effects of the inundations in these two rivers is very remarkable. In the one it distributes health and plenty; in the other, disease, famine, and death. The inhabitants along the torrid shores of the Senegal, can receive no benefit from any additional manure the river may carry down to their soil, which is by nature more than sufficiently luxuriant; or even if they could, they have not industry enough to turn it to advantage. The banks of the river, therefore, lie uncultivated, overgrown with rank and noxious herbage, and infested with thousands of animals of various malignity. Every new Hood only tends to increase the rankness of the soil, and to provide fresh shelter for the creatures that harbour there. If the flood continues but a few days longer than usual, the improvident inhabitants, who are driven up into the higher grounds, want provisions, and a famine
When the river begins to return into its channel, the humidity and heat of the air are equally pernicious; and the carcasses of animals, swept away by the inundation, putrifying in the sun, produce a stench that is almost insupportable. Even the luxuriance of the vegetation becomes a nuisance; the smell of some of the