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DESCRIPTION OF AMERICA.

BOUNDARIES AND EXTENT.

A HIS vast country extends from the 8oth degree of north, to the 56th degree of south latitude; and, where its breadth is known, from the 35th to the »36th degree west longitude from London; stretching between 8000 and 9000 miles in length, and in its greatest breadth 3690. It fees both hemispheres, has two summers and a double winter, and enjoys all the variety of climates which the earth affords. It is washed by the two great oceans. To the eastward it has the Atlantic, uhich divides it from Europe and Africa; to the west it has the Pacific wGreat South Sea, by which it is separated from Asia. By these seas it may, and does, carry on a direct commerce with the other three part* of the world.

North And South Continent. America is not of equal breadth throughout its whole extent; but is divided into two great continents, called North and South America, by an isthmus 1500 miles long, and which at Darien, about Lat. 90 N. is only 60 miles over. This isthmus forms, with the northern and southern continents, a vast gulph, in which lie a great number of islands, called the Weft Indies, in contradistinction to the eastern parts of Asia, which are called the East Indies.

Climate. Between the New World and the Old, there are several very striking differences; but the most remarkable is the general predorhinance of cold throughout the whole extent of America. Though we cannot, in any country, determine the precise degree of heat merely by the distance of the equator, because the elevation above the sea, the nature of the soil, &c. affect the climate; yet, in the ancient continent, $he heat is much more in proportion to the vicinity to the equator than in any part of America. Here the rigour of the frigid zone extends ovei half fhat which should be temperate by its position. Even in thefts

latitudes

latitudes where the winter is scarcely felt on the Old continent, it reign* with great severity in America, though during a short period. Nor does this cold, prevalent in the New World, confine itself to the tempe. rate zones; but extends its influence to the torrid zone, also, consider. ably mitigating the excess of its heat. Along the eastern coast, the climate, though more similar to that of the torrid zone in other parts of the earth, is nevertheless considerably milder than in those countries of Asia and Africa which lie in the fame latitude. From the southern tropic to the extremity of the American continent, the cold is said to be much greater than in parallel northern latitudes even of America itself.

For this so remarkable difference between the climate of the Neir continent and the Old, various causes have been assigned by different authors. The following is the opinion of the learned Dr. Robertson on this subject. "Though the utmost extent of America towards the north be not yet discovered, we know that it advances nearer to the pole than either Europe or Asia. The latter have large seas to the north, which are open during part of the year; and, even when covered with ice, the wind that blows over them is less intensely cold than that which blows over land in the fame latitudes. But, in America, the land stretches from the river St. Laurence towards the pole, and spreads out immensely to the west. A chain of enormous mountains, covered with snow and ice, runs through all this dreary region. The wind passing over such an extent of high and frozen land, becomes so impregnated with cold, that it acquires a piercing keenness, which it retains in its progress through warmer climates; and is not entirely mitigated until it reach the gulph of Mexico. Over all the continent of North America, a north-westerly wind and excessive cold are synonymous terms. Even in the most sultry weather, the moment that the wind veers to that quarter, its penetrating influence is felt in a transition from heat to cold no less violent than sudden, To this powerful cause we may ascribe the extraordinary dominion of cold, and its violent in-roads into the southern provinces in that part of the globe.

"Other causes, no less remarkable, diminish the active power os heat in those parts of the American continent which lie between the tropics. In all that portion of the globe, the wind blows in an invariable direction from east to west. As this wind holds its course across the ancient continent, it arrives at the countries which stretch along the western shore, of Africa, inflamed with all the fiery particles which it hath collected from the sultry plains of Asia, and the burning sands in the African desarts. The coast of Africa is accordingly the region of the earth which feels.

the fie most fervent heat, and is exposed to the unmitigated ardour of the torrid zone. But this fame wind, which brings such an accession of warmth to the countries lying between the river of Senegal and Casraria, ■ traverses the Atlantic ocean before it reaches the American shore. It is cooled in its passage over this vast body of water; and is felt as a refreshing gale along the Coasts of Brasil and Guiana, rendering those countries, though amongst the warmest in America, temperate, whea compared with those which lie opposite to them in Africa. As this wind advances in its course across America, it meets with immense plains covered with impenetrable forests; or occupied by large rivers, marshes, and stagnating waters, where it can recover no considerable degree of heat. At length it arrives at the Andes, which run from north to south through the whole continent. In passing over their elevated and frozen summits, it is so thoroughly cooled, that the greater part of the countries beyond them hardly feel the ardour to which they seem exposed by their situation. In the other provinces of America, from. Terra Firma westward to the Mexican empire, the heat of the climate is tempered, in some places, by the elevation of the land above the sea; in others, by their extraordinary humidity; and in all, by the enormous mountains scattered over this tract. The islands of America in the torrid zone are either small or mountainous, and are fanned alternately ty refreshing sea and land breezes.

"The causes of the extraordinary cold towards the southern limits of America, and in the seas beyond it, cannot be ascertained in a manner equally satisfying. It was long supposed, that a vast continent, distinguished by the name of Terra Aujlralis Incognita, lay between the southern extremity of America and the antarctic pole. The same principles which account for the extraordinary degree of cold in the northern regions of America, were employed in order to explain that which is felt at Cape Horn and the adjacent countries. The immense extent of the southern continent, and the rivers which it poured into the ocean, were mentioned and admitted by philosophers as causes sufficient to octasion the unusual sensation of cold, and the still more uncommon appearances of frozen seas in that region of the globe. But the imaginary continent to which such influence was ascribed having been searched for in vain, and the space which it was supposed to occupy having been found to be an open sea, new conjectures must be formed with respect to the causes of a temperature of climate, so extremely different from that which we experience ia countries removed at the fame distance from the opposite pole. No. II. M '"The

"The most obvious and probable cause of this superior degree of Com towards the southern extremity of America, seems to be the form of the continent there. Its breadth gradually decreases as it stretches from St. Antonio southwards, and from the bay of St. Julian to the straits of Magellan its dimensions are much contracted. On the east and west fides, it is warned by the Atlantic aud Pacific oceans. From its southern point, it is probable that an open sea stretches to the antarctic pole. In whichever of these directions the wind blows, it is cooled before it approaches the Magellanic regions, by passing over a vast body of water; nor is the land there of such extent, that it can recover any considerable degree of heat in its progress over it. These circumstances concur in rendering the temperature of the air in this district of America more similar to that of an insular, than to that os a continental climate; and hinder it from acquiring the same degree of summer-heat with places in Europe and Asia, in a corresponding northern latitude. The north wind is the only one that reaches this part of America, after blowing over a grwt continent. But, from an attentive survey of its position, this will be found to have a tendency rather to diminish than augment the degree of heat. The southern extremity of America is properly the termination of the immense ridge of the Andes, which stretches nearly io a direct line from norrti to souths through the whole extent of the continent. The most sultry regions in South America, Guiana, Brasil, 'Paraguay, and Tucuman, lie many degrees to the east of the Magellanie regions. The level country of Peru, which enjoys the tropical heats, ii situated considerably to the west of them. The north wind, then, though it blows over land, does not bring to the southern extremity of America an increase of heat collected in its passage over torrid regions; but, before it arrives there, it must have swept along the summit of the Andes, and come impregnated with the cold of that frozen region."

Another particularity in the climate of America, is its excessive moisture in general. In some places, indeed, on the western coast, rain not known; but, in alt other parts, the moistnese of the climate is as remarkable as the cold.—The forests wherewith it is every where covered, no doubt, partly occasion the moisture of its climate; but the most prevalent cause is the vast quantity of water in the Atlantic and Pacific oceans, with which America is environed on all fides. Hence those places where the continent is narrowest are deluged with almost perpetual rains, accompanied with violent thunder and lightning, by which some of them, particularly Potto Bello> are rendered in a maaneT

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This extreme moisture of the American climate is productive of much larger rivers there than in any other part of the world. The Danube, the Nile, the Indus, or the Ganges, are not comparable to the Mississippi, the river St. Laurence, or that of the Amazons; nor are such large lakes to be found any where as those which North America affords. To the fame cause we are also partly to ascribe the excessive luxuriance of all kinds of vegetables in almost all parts of this country. In the southern provinces, where the moisture of the climate is aided by the warmth of the fun, the woods are almost impervious, and the surface of the ground is hid from the eye, under a thick covering of shrubs, herbs, and weeds.—In the northern provinces, the forests are not encumbered with the fame luxuriance of vegetation; nevertheless, they afford trees much larger of their kind than what are to be found any where else.

From the coldness and the moisture of America, an extreme malignity of climate has been- inferred, and asserted by M. de Paw, in his Rtchercbcs Philofiphiques. Hence, according to his hypothesis, the smallness and irregularity of the nobler animals, and the size aud enormous multiplication of reptiles and insects.

But the supposed smallness and less ferocity of the American animals, file Abbe Clavigero observes, instead of the malignity, demonstrates the mildness and bounty of the clime, if we give credit to Buffon, at whose fountain M. de Paw has drank, and of whose testimony he has availed himself against Don Fernetty. Buffon, who in many places of his Natural History produces the smallness of the American animals as a certain argument of the malignity of the climate of America, in treating afterwards of savage animals, in Tom. II. speaks thus: "As all tilings, even the most free creatures, are subject to natural laws, and animals as Well as men are subjected to the influence of climate and soil, it appears that the fame causes which have civilized and polished the human soecits in our climates, may have likewise produced similar effects upon other species. The wolf, which is perhaps the fiercest of all the quadrupedsof the temperate zone, is however incomparably less terrible than the tyger, the lion, and the panther, of the torrid zone; and the white bear and hyena of the frigid zone. In America, where the air and the earth are more mild than those of Africa, the tyger, the lion, and the panther, are not terrible but in the name. They have degenerated, is fierceness, joined to cruelty, made their nature; or, to speak more properly, they have only suffered the influence of the climate: under a milder Iky, their nature also has become more mild. From climes which are immoderate in their temperature, are obtained drugs, perfumes, poisons,

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