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GENERAL

DESCRIPTION OF AMERICA,

BOUNDARIES AND EXTENT.

THIS vaft country extends from the 80th degree of north, to the

56th degree of fouth latitude; and, where its breadth is known, from the 35th to the 136th degree weft longitude from London; ftretching between 8000 and 9000 miles in length, and in its greatest breadth 3690. It fees both hemifpheres, has two fummers 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, which divides it from Europe and Africa; to the weft it has the Pacific or Great South Sea, by which it is feparated from Afia. By thefe feas it may, and does, carry on a direct commerce with the other three parts

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 ifthmus 1500 miles long, and which at Darien, about Lat. 9° N. is only 60 miles over. This ifthmus forms, with the northern and fouthern continents, a vast gulph, in which lie a great number of islands, called the West Indies, in contradiftinction to the eastern parts of Afia, which are called the East

Indies.

CLIMATE. Between the New World and the Cld, there are feveral very ftriking differences; but the most remarkable is the general predominance of cold throughout the whole extent of America. Though we cannot, in any country, determine the precife degree of heat merely by the distance of the equator, because the elevation above the sea, the nature of the foil, &c. affect the climate; yet, in the ancient continent, the 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 over half that which should be temperate by its pofition. Even in those

latitudes

latitudes where the winter is fcarcely felt on the Old continent, it reigns with great feverity in America, though during a fhort period. Nor does this cold, prevalent in the New World, confine itself to the temperate zones; but extends its influence to the torrid zone, alfo, confiderably mitigating the excefs of its heat. Along the eastern coaft, the climate, though more fimilar to that of the torrid zone in other parts of the earth, is nevertheless confiderably milder than in thofe countries of Afia and Africa which lie in the fame latitude. From the fouthern tropic to the extremity of the American continent, the cold is faid to be much greater than in parallel northern latitudes even of America itself,

For this fo remarkable difference between the climate of the New continent and the Old, various caufes have been affigned by different authors. The following is the opinion of the learned Dr. Robertfon on this fubject." Though the utmoft extent of America towards the north be not yet difcovered, we know that it advances nearer to the pole than either Europe or Afia. The latter have large feas to the north, which are open during part of the year; and, even when covered with ice, the wind that blows over them is lefs intenfely 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 immenfely to the weft. A chain of enormous mountains, covered with fnow and ice, runs through all this dreary region. The wind paffing over fuch an extent of high and frozen land, becomes fo impregnated with cold, that it acquires a piercing keennefs, which it retains in its progrefs through warmer climates; and is not entirely mitigated until it reach the gulph of Mexico. Over all the continent of North America, a north-wefterly wind and exceffive cold are fynonymous terms. Even in the most fultry weather, the moment that the wind veers to that quarter, its penetrating influence is felt in a tranfition from heat to cold no lefs violent than fudden, To this powerful caufe we may afcribe the extraordinary dominion of cold, and its violent in-roads into the fouthern provinces in that part of the globe.

“Other caufes, no lefs remarkable, diminish the active power of heat in thofe 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 caft to weft. As this wind holds its courfe 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 fultry plains of Afia, and the burning fands in the African defarts. The coast of Africa is accordingly the region of the earth which feels

the

the most fervent heat, and is expofed to the unmitigated ardour of the torrid zone. But this fame wind, which brings fuch an acceffion of warmth to the countries lying between the river of Senegal and Cafraria, traverfes the Atlantic ocean before it reaches the American fhore. It is cooled in its paffage over this vaft body of water; and is felt as a refreshing gale along the coafts of Brafil and Guiana, rendering those countries, though amongst the warmeft in America, temperate, when compared with those which lie oppofite to them in Africa. As this wind advances in its courfe across America, it meets with immense plains covered with impenetrable forefts; or occupied by large rivers, marthes, and ftagnating waters, where it can recover no confiderable degree of heat. At length it arrives at the Andes, which run from north to fouth through the whole continent. In paffing over their elevated and frozen fummits, it is fo thoroughly cooled, that the greater part of the countries beyond them hardly feel the ardour to which they feem. expofed by their fituation. In the other provinces of America, from Terra Firma weftward to the Mexican empire, the heat of the climate is tempered, in fome places, by the elevation of the land above the fea; in others, by their extraordinary humidity; and in all, by the enormous mountains fcattered over this tract. The islands of America in the torrid zone are either fmall or mountainous, and are fanned alternately by refreshing fea and land breezes.

"The caufes of the extraordinary cold towards the fouthern limits of America, and in the feas beyond it, cannot be ascertained in a manner equally fatisfying. It was long fuppofed, that a vast continent, diftinguished by the name of Terra Auftralis Incognita, lay between the fouthern extremity of America and the antarctic pole. The fame 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 immenfe extent of the fouthern continent, and the rivers which it poured into the ocean, were mentioned and admitted by philofophers as caufes fufficient to occafion the unufual fenfation of cold, and the ftill more uncommon appearances of frozen feas in that region of the globe. But the imaginary continent to which fuch influence was afcribed having been fearched for in vain, and the fpace which it was fuppofed to occupy having been found to be an open sea, new conjectures must be formed with respect to the caufes of a temperature of climate, fo extremely different from that which we experience in countries removed at the fame distance from the oppofite pole.

No. II.

M

<< The

"The most obvious and probable caufe of this fuperior degree of cold towards the southern extremity of America, feems to be the form of the continent there. Its breadth gradually decreafes as it ftretches from St. Antonio fouthwards, and from the bay of St. Julian to the ftraits of Magellan its dimenfrons are much contracted. On the eaft and weft fides, it is washed by the Atlantic and Pacific oceans. From its fouthern point, it is probable that an open fea ftretches to the antarctic pole. In whichever of thefe directions the wind blows, it is cooled before it approaches the Magellanic regions, by paffing over a vaft body of water; nor is the land there of fuch extent, that it can recover any confiderable degree of heat in its progrefs over it. Thefe circumftances concur in rendering the temperature of the air in this diftrict of America more funilar to that of an infular, than to that of a continental climate; and hinder it from acquiring the fame degree of fummer-heat with places in Europe and Afia, in a correfponding northern latitude. The north wind is the only one that reaches this part of America, after blowing over a great continent. But, from an attentive furvey of its pofition, this will be found to have a tendency rather to diminish than augment the degree of heat. The fouthern extremity of America is properly the termination of the immenfe ridge of the Andes, which stretches nearly in a direct line from north to fouth, through the whole extent of the continent. The moft fultry regions in South America, Guiana, Brafil, Paraguay, and Tucuman, lie many degrees to the east of the Magellanis regions. The level country of Peru, which enjoys the tropical heats, is fituated confiderably to the weft of them. The north wind, then, though it blows over land, does not bring to the fouthern extremity of America an increafe of heat collected in its paffage over torrid regions; but, before it arrives there, it must have swept along the fummit of the Andes, and come impregnated with the cold of that frozen region.”

Another particularity in the climate of America, is its exceffive moifture in general. In fome places, indeed, on the western coaft, rain is not known; but, in all other parts, the moiftness of the climate is as remarkable as the cold.-The forefts wherewith it is every where covered, no doubt, partly occafion the moisture of its climate; but the moft prevalent caufe is the vast quantity of water in the Atlantic and Pacific oceans, with which America is environed on all fides. Hence thofe places where the continent is narroweft are deluged with almoft perpetual rains, accompanied with violent thunder and lightning, by which fome of them, particularly Porto Bello, are rendered in a mannes uninhabitable.

This extreme moifture 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 Miffiffippi, the river St. Laurence, or that of the Amazons; nor are fuch large lakes to be found any where as thofe which North America affords. To the fame caufe we are alfo partly to afcribe the exceffive luxuriance of all kinds of vegetables in almoft all parts of this country. In the fouthern provinces, where the moisture of the climate is aided by the warmth of the fun, the woods are almost impervious, and the furface of the ground is hid from the eye, under a thick covering of fhrubs, herbs, and weeds. In the northern provinces, the forefts 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 coldnefs and the moisture of America, an extreme malignity of climate has been inferred, and afferted by M. de Paw, in his Recherches Philofophiques. Hence, according to his hypothefis, the smallnefs and irregularity of the nobler animals, and the fize and enormous multiplication of reptiles and infects.

But the fuppofed fmallness and lefs ferocity of the American animals, the Abbé Clavigero obferves, instead of the malignity, demonstrates the mildness and bounty of the clime, if we give credit to Buffon, at whofe fountain M. de Paw has drank, and of whofe teftimony he has availed. himfelf against Don Pernetty. Buffon, who in many places of his Natural History produces the fmallness of the American animals as a certain argument of the malignity of the climate of America, in treating afterwards of favage animals, in Tom. II. fpeaks thus: "As all things, even the most free creatures, are fubject to natural laws, and animals as well as men are subjected to the influence of climate and foil, it appears that the fame caufes which have civilized and polished the human fpecies in our climates, may have likewife produced fimilar effects upon other fpecies. The wolf, which is perhaps the fierceft of all the quadrupeds of the temperate zone, is however incomparably lefs 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 thofe of Africa, the tyger, the lion, and the panther, are not terrible but in the name. They have degenerated, if fiercenefs, joined to cruelty, made their nature; or, to fpeak more properly, they have only fuffered the influence of the climate: under a milder sky, their nature alfo has become more mild. From climes which are im. moderate in their temperature, are obtained drugs, perfumes, poisɔns,

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