that it would have been upset by any one rising imprudently from his seat, without warning the rowers to preserve its balance by leaning to the opposite side. We had suffered severely from the stings of insects, but had withstood the insalubrity of the climate; we had passed without accident the numerous falls and bars that impede the navigation of the rivers, and often render it more dangerous than long voyages by sea. After all we had endured, I may be allowed to mention the satisfaction which we felt in having reached the tributaries of the Amazon." The Rio Negro, which flows into that river, was navigated downwards as far as San Carlos, then supposed to lie under the equator, but actually about 2° N. From thence the travellers retraced the river, passed from it into the Cassiquiare, and again entered the main channel of the Orinoco, three leagues below the mission of Esmeralda; thus demonstrating a junction between the two great floods of the Amazon and Orinoco, which had been, in the year 1798, declared by Bauche to be a geographical monstrosity. The bifurcation of the Orinoco takes place in the following manner:-The river, issuing from among the mountains, reaches the opening of a valley or depression which terminates at the Rio Negro. Here it divides into two branches, the smaller, or the Cassiquiare, turning off to the south, while the main stream continues its original direction-west-north-west. A reference to Humboldt's map, of which we give a translated copy, will render further explanation unnecessary.

The preceding notices refer to what have been appropriately styled the "might rivers," and the "great rivers," none of which are to be found in Europe. Its noblest running waters belong to a third grade. "These," says Inglis, "I would designate the large rivers; for great and large are not entirely synonymous; and, to most minds, the term great river and large river, will present a distinct image. The lower we descend in the scale, the more numerous do we find the species. The continent of Europe abounds with examples of the third class-such as the Rhine, the Danube, the Rhone, the Elbe, the Tagus, the Ebro, and the Guadalquivir. The fourth class is still more numerous; and of this class, which I would call considerable rivers, we may find examples at home. Father Thames takes the lead; and the Severn, and perhaps the Trent, the Clyde, the Tweed, the Tyne, and the Tay, may be entitled to the same distinction. On the Continent, it would be easy to name a hundred such; let me content myself with naming the Loire, the Meuse, the Saone, the Garonne, the Adige, and the Maine. Fifthly, come the small rivers. Multitudinous they are; but as examples, I may name the Wye, the Dart, the Derwent, the Dee, the Aire, the Spey, the Ex, and a thousand such; while on the continent, of the same class, may be mentioned the Gare, the Seine, the Reuss, or the Sambre. The word river can no longer be employed, for now come the family of streams-nameless, except to those who live upon their banks: the rivulets follow; and, lastly, we close the enumeration with rills." The small rivers, with the streams subordinate to them, are especially rife in countries where there is the vicinage of the sea, and high elevations on the land. This renders them so abundant in such districts as the Greek peninsula. There, Alpine tracts of territory collect from the atmosphere the vapours of the contiguous sea, arrest the castellated glories of cloud-land, and awaken in the valleys and plains the refreshing music of the voice "of many waters." The commerce of kingdoms distinguishes not the rivers of this classic soil, but they are familiar with the charms of nature, add effect to the sublime and wild in its scenery, and clothe with heightened grace the soft and pastoral. Following the course of the Angitas up to its source, we come to one of the most picturesque sites in Macedonia, supposed to be the nymphæum or grotto of Onocaris. Blocks of marble, rudely piled, as if tossed together by an earthquake, obstruct its entrance, which can only be passed in a crawling posture; but these difficulties being overcome, a cave like a temple appears, from the farther end of which runs the limpid stream, flowing silently over a sand bed, but rippling when it escapes

from the grotto. In a recess, there are some remains of ancient masonry below an aperture, through which a mysterious light finds its way.

Upon the large circular valley-plain of Boeotia, the heights of Parnassus on the west, Helicon on the south, and Citharon on the east, send down streams, covering the undulating surface of this Classic Land with a life-sustaining vegetation. The same physical causes high lands and the contiguous sea- operate, in Judea as in Greece, to render it a well-watered country-a "land of brooks," according to its scripture designation. There are no considerable rivers, owing to the scanty extent of its hydrographical basins; but the melting of the snow on the high mountains of Syria, and the periodical sound of an "abundance of rain," contribute to furnish an ample irrigation. Its principal stream-the Jordan-though only one of the fifth class, and not remarkable for picturesque beauty except in the upper part of its course, has a sacred and historic interest which will always strongly attract attention to it, while it exhibits a singular physical peculiarity. This is the depression of the valley, in which it flows, below the level of the Mediterranean, through the whole distance between the Sea of Tiberias and the Dead Sea; and the great inclination of its descent from the one to the other, amounting at a mean to very nearly eighteen feet per mile. Hence the force of its current, notwithstanding a comparatively small volume of water, and the few windings that mark its channel. Speaking of its appearance near the site of Jericho, Dr. Robinson states: "There was a still though very rapid current. We estimated the breadth of the

stream to be from eighty to one hundred feet. The guides supposed it now to be ten or twelve feet deep. The current was so strong, that even Komeh, a stout swimmer of the Nile, was carried down several yards in crossing." Upon the authority of some phrases in the English version of the Scriptures, which perhaps do not express the sense of the original Hebrew, it has been generally supposed that the Jordan periodically inundated the country in its neighbourhood, at, and for some time after, the Israelitish conquest of it. If this were so, either the river must have worn for itself a deeper bed, or the quantity of rain in Palestine must have largely diminished, for there is now no overflow of its banks. At present, the "swellings of Jordan"- -one of the phrases alluded to-amount only to a slight annual rise. Copious rains descend upon the mountains round its sources, and the melting of the snows of Lebanon supply numerous temporary torrents; but these contributions are received into the capacious basins of the lakes Merom and Tiberias, and are there spread over an extensive surface, so as to prevent the level of the river from rising into inundation.

In exactly the same manner, the great Canadian lakes prevent any rise to the St. Lawrence, by the immense floods that rush into them in the spring spreading over their vast beds, and producing only an almost inappreciable elevation of their level. Lebanon,

the feeder of the Jordan from its internal reservoirs, along with "Abana and Pharpar, rivers of Damascus," and the Orontes, gives birth to many rapid and brawling streams, and a thousand cascades, when its snows melt, which strikingly display the erosive power of running water. Deep passages have been cut in the rocks, bestrided by natural arches, like the rock-bridge of Virginia. Of this description is the natural bridge over the Ain el Leban, rising nearly two hundred feet above the torrent which has gradually dug the excavation, as annually the spring has renewed its strength. The brook flows into the Beyrout river, and its channel would be quite dry in summer, were it not for the impediments its mountain course presents. It was the spring season, the time of the melting of the snow, when the monarch of Israel, during his temporary exile from the throne, retreated for a refuge towards the fastnesses of Lebanon. He saw the torrents falling

from height to height into the valleys. He heard the voices of the waters as they leaped from rock to rock. His imagination converted this external scenery into a picture of the force of his adversities; and hence the allusion, in the plaintive elegiac, commemorative of his condition, to the "noise of cataracts," and to "deep calling unto deep."

In advancing towards their termination, and at their embouchure, the great rivers present several striking peculiarities. It has already been remarked, that a junction of two large streams often occurs without any expansion of the surface of their waters being the consequence, but a greater velocity of current and depth of channel. In some cases, instead of a wider course being created by increased volume of water, there is actually a narrower bed. Thus the Mississippi is a mile and a half wide, and the Missouri half a mile wide, at their confluence, yet from that point to the mouth of the Ohio, the medium width of the united rivers is but three quarters of a mile, and through the lower parts of its course the main stream has, if any thing, a less surface-breadth, though vast accessions are made to it by the Arkansas, Red River, and others of great depth and body of water. Most of the tributaries of the Mississippi also are wider a thousand miles apart from it than at the point of junction, and the same feature is characteristic of other great streams, that as they increase their volume of water, and approach their termination, they flow in narrower though deeper channels. The Nile is not so broad at Cairo as at Siout, nor so broad at Siout as at Thebes. At Assouan, high up the stream, it is 3900 feet wide; at Oudi, 36 miles above Cairo, it is 2900; and at Rosetta, near its mouth, but 1800. This is one of the many examples of benign adjustment with which the realms of nature teem; for hereby, a rich legacy of fertile soil, usually found at the mouths of rivers, is saved from submergence, and becomes the inheritance of man. In their junction with the sea, rivers display the diversity of sometimes pouring forth their waters through a single mouth, and distributing them into a variety of channels; circumstances mainly dependent upon the country through which they flow being easily susceptible of excavation or not, and upon the power of the stream. The Ganges pours its flood through the many channels here represented. The Volga is celebrated for its seventy mouths; and the Rhine, the Nile, Mississippi, and Orinoco pour out their current through several branches. The space enclosed within these various channels is called a delta,

Patna

Ganges

Hoogly

Calcutta

Dacca

from its triangular form, and general resemblance to the shape of the Greek letter A. So powerfully do many of the great rivers rush into the ocean, that their waters are distinct from those of the briny deep, when out of sight of the land. A British fleet lying opposite to the mouth of the Rhone occasionally took up fresh water at a considerable distance from the shore; and Columbus found his vessel in the fresh water of the Orinoco before he discovered the continent of South America. The collision of a great river current and the opposing tide of the sea is sometimes so violent as to occasion an elevated ridge of waters, heaving and tossing in a tremendous manner, shattering to pieces the illfated vessel that comes into contact with it. The passage of the Garonne into the Bay of Biscay, and of the Ganges into the Bay of Bengal, exhibit this phenomenon. Upon the rivers meeting the advancing tides, a conflict ensues for the mastery, and the force of the sea triumphing in the struggle, often sends a mountain-wave up the streams, overturning boats, inundating the banks, and causing extensive destruction. The most remarkable example of this struggle for empire, between the waters of the land and of the deep, occurs off the mouth of the Amazon, and is the Indian pororoca. When

the tide flows out of the river, it pours forth its unshackled current with greater fury, and meeting at right angles with the ocean current that runs from Cape St. Roque along the north-east coast of Brazil, the shock of these two bodies raises their waters into an embankment, upwards of a hundred feet in height. The roar of the clashing waves is heard for miles around, and the fishermen and mariners fly in terror from the scene till the strife is over, speedily to be renewed.

In treating of the magnitude of rivers, some writers refer to the elevation of the range of mountains from which they descend; and it is obviously true, that the greater the height of the mountains, the more extensive are their snows and glaciers, and the larger the supply of water furnished by springs and torrents. But the magnitude of a stream is more especially regulated by the extent of country which forms the declivities of its basin, though there is no invariable proportion here, for a small basin in a humid region will yield a greater quantity of water than one much more considerable in a different situation. High mountains, a humid climate, and a wide superficial drainage, are the three physical circumstances which lead to the accumulation of vast bodies of water, the magnitude of which will be proportionate to the degree in which these causes are in combined operation. Upon the surface of the New World, we have these causes acting with greater intensity than upon that of the Old, which explains the superior character of the streams of the western continent. The following table exhibits the extent of the hydrographical regions of the principal rivers of the globe, with the proportionate size of their basins :

Rivers, according to their termination, may be grouped in two grand classes, the continental and the oceanic. The continental are those which have no communication at all with the ocean, but discharge their waters into completely insulated lakes, or lose themselves in sands and swamps. Thus the Volga, Kour, Terek, and Ural, terminate in the Caspian; the Amou, or Jihoon (ancient Oxus), the Sir, or Sihoon (ancient Jaxartes), flow to Lake Aral; and the Jordan finishes its course in the Dead Sea. On the lofty tablelands of Mexico, Bolivia, and Central Asia, there are respectively the Rio Grande, Desaguadero, and Yarkand, which are entirely confined to those elevated regions, termi