THE ARGENTINE REPUBLIC comprises the greater part of what was formerly.the Spanish viceroyalty of Buenos Ayres. On the separation of the country from Spain the remainder of the viceroyalty seceded from the authority of the government established at Buenos Ayres, and formed the three important republics of Bolivia, Paraguay, and the Banda Oriental del Uruguay, commonly called either the Oriental Republic or Uruguay. The city of Buenos Ayres, the capital of the province of the same name, then became the seat of the national government of the United Provinces of the Rio de la Plata,—so named in the treaty with England, by which their independence was recognised, and since termed the Argentine Republic. Including the Indian tribes, who are in almost undisputed possession of half its territory, the country does not contain half so many inhabitants as the city of London, though it extends over an area as great as all Central and Western Europe combined; and the fertility of its vast plains, together with the yet undeveloped wealth of its mineral resources, indicate that it is well able to sustain as numerous a population as that of the part of Europe just alluded to. Its extent in latitude is greater than that of any other existing country, if we except the comparatively useless foreign regions of British America and those of the Russian empire, though it only slightly exceeds that of the comparatively narrow slip of land which forms the neighbouring Republic of Chili. It is bounded on the W. by Chili; on the S. by the Strait of Magellan; on the E. by the Atlantic Ocean, the Oriental Republic, the Empire of Brazil, and the Republic of Paraguay; and on the N. by the Republic of Bolivia. The boundary to the W. is formed by the mountain chain of the Andes. The southern limit is at present a question in dispute with the Government of Chili, who claim the entire extent of the Strait of Magellan; but it is probable that the Argentine Government will make good its claim to the eastern portion. The broad stream of the Uruguay below its tributary, the Guarey, or Cuareim, divides it from the Oriental Republic, except that the small but important island of Martin Garcia, close to the Oriental shore of the Uruguay at its junction with the Parana, belongs to the Argentine Republic. The boundary with Brazil is then formed by the Uruguay and its tributary, the Pepiri Guazu, from the head waters of which it crosses the Sierra de los Missiones to the head waters of the San Antonio Guazu, the course of which it follows, and then that of the Iguazu, or Rio Grande de Caritiba, an important tributary of the Parana. The Parana, down to its junction with the Paraguay, and the latter upwards as far as the mouth of the Pilcomayo, form the boundary with the Republic of Paraguay. South of the 22d degree of latitude the country between the Pilcomayo and the Paraguay is disputed by the Argentine Republic and Paraguay. The boundary with Bolivia lies along the 22d degree of latitude between the Pilcomayo and the Vermejo, and then, leaving important tributaries of the latter to Bolivia, it follows the course of that river to its source, whence it takes a devious course westwards among the mountains which form spurs to the Andes. On reaching the latter it follows the main chain southwards to latitude 25° 30', where it passes to a more westerly ridge of the Andes on which the boundaries of the three neighbouring republics unite. The boundary we have described with Bolivia cannot be considered as permanently settled; and the boundary between Bolivia and Paraguay to the north of the Argentine Republic has not been determined. The boundary questions with all these republics are in an unsatisfactory state.

The most remarkable feature of the country is its plains, which may be said to extend over more than three-fourths of it. The plains of Patagonia in the south, the Pampas across the extending central part of the country, and the Chaco in the north-east, have no very definite natural boundaries. The two latter are, in fact, the same continuous formation, in which a slight undulation divides the streams of the Chaco, which join the Parana, from those of the Pampas, which either flow into the Atlantic south of the mouth of the latter river, or disappear by absorption into the soil, and evaporation as they spread over the plains. The best parts of these plains are covered with a rich alluvial soil from 3 to 6 feet in thickness, formed by the constant decaying of the luxuriant vegetation which grows upon it, and this soil rests upon a sedimentary deposit of earth, which appears to have been scoured away from the Andes and the high lands of the central part of the continent. A great part of Patagonia and the western Pampas consists of gravel and coarse detritus from the Andes, and, though apparently sterile, only requires irrigation to become productive. Other parts of the plains are dry, saline wastes or brackish marshes, which probably mark the former position of an inland sea. Excepting the hills in the south of the province of Buenos Ayres and those of Cordova, the mountain districts of the country consist of the eastern elope of the gigantic range of the Andes and its branches, which latter make all the north-western part of the country a mountainous region. The great chain of the Andes consists of a confused mass of broken and contorted strata, piled upon an elevated ridge of granite, through which numerous volcanoes, many of them still active, have ejected vast quantities of lava and scoriae. Along most parts of the great mountain chain there are three subsidiary and more or less parallel ridges, between which fertile valleys are formed in many places, whilst in other parts the separation between them is not very clearly defined. In the north-west the boundary with Bolivia lies along the most eastern of the ridges just mentioned, so that the valleys to the west of it are within that republic, but the boundary with Chili lies along the western ridge, so that the central and eastern ridges, with the fine valleys which lie between them, belong to the Argentine Republic. The great chain of the Andes, as described by Mr Evan Hopkins, who made extensive explorations in various parts of it, is formed of innumerable varieties of granite, gneiss, schists, hornblende, chloritic slates, porphyries, <fcc., and these rocks alternate with each other in great meridional bands. The crystalline rocks follow no particular order in the alternation. For miles only granite and gneiss are found, and again schist, quartz, gneiss, <kc., intervening, l The whole of the crystalline rocks, especially the micaceous l variety, pass insensibly from the crystalline to the laminated structure. We have first the granite base, in which the crystals are somewhat confusedly mixed; these gradually become arranged upwards into parallel lines, and the rock is then called gneiss; by degrees the felspar is decomposed, and the mass becomes schistose, with enclosed veins of the predominating element of the compound below. This is the general character of the primary structure of the Andes, and upon it there are many bits of sandstones, limestones, <fcc., especially on the eastern chain.

9 The most careful and elaborate researches into the geological conformation of the country were made by Mr Darwin, who published the results in his work on the geology of South America. He points out evidences of a gradual upheaval of the plains of Patagonia and the Pampas, to the extent of 400 feet in the southern part of the former, and 100 feet in the latter district. The Pacific and Atlantic Oceans were once connected through what is at present the basin of the Santa Cruz river, in latitude 50° S. This latter district appears to have been upheaved at least 1400 feet before the period of the gradual upheaval above mentioned, as indicated by the present position of gigantic boulders, which have been transported on icebergs 60 and 70 miles from their parent rock. The enormous layers of gravel and sand, on the plains and even on the hills of eastern Patagonia, give evidence of its having at one time formed the bed of an ocean which rolled against the Audes or intervening ranges of mountains. The characteristic feature of the plains of Patagonia is gravel, whereas that of the Pampean formation, which includes the Chaco, is earth which, according to Mr Darwin’s lucid arguments, has been deposited in the form of sand in the estuary of the River Plata, the position of which has been continually changing in consequence of the gradual upheaval of the country. This formation extends to the south-west and north-west from the present estuary, over an area at least 750 miles long and 400 miles broad, and the thickness of the deposit is from 30 to 100 feet. The hills of Tapalquen, Tandil, and Vulcan, composed of unstratified granular quartz, project through the eastern part of this Pampean formation. The higher range of the Sierra Ventana further south is also quartz. South of the Sierra Ventana, for a distance of 380 miles, crystalline rocks are seldom if ever met with on the east coast; and beyond that a porphyritic formation is found resembling the lowest stratified formation of the Andes.

“The highest peaks of the Cordillera, ’ says Mr Darwin, “appear to consist of active, or more commonly, dormant volcanoes—such as Tupungato, Maypu, and Aconcagua, which latter stands 23,000 feet above the level of the sea, and many others. The next highest peaks are formed of the gypseous and porphyritic strata, thrown into vertical or highly inclined positions. . . . This grand range has suffered both the most violent dislocations, and slow, though grand, upward and downward movements in mass: I know not whether the spectacle of its immense valleys, with mountain masses of once-liquefied and intrusive rocks now bared and intersected, or whether the view of those plains, composed of shingle and sediment hence derived, which stretch to the borders of the Atlantic Ocean, is best adapted to excite our astonishment at the amount of wear and tear which these mountains have undergone. "

We commend Mr Darwin’s work to the attention of readers desirous of becoming better acquainted with the geological conformation of the Argentine Republic.

The great extent of this country in latitude makes its climate range through all diversities of temperature from that of Northern Europe and Canada to that of Egypt and Arabia. The climate of Southern Patagonia is less intemperate than that of Labrador at the same distance from the equator in the northern hemisphere, but colder than the Atlantic shores of Europe in the same latitude. As the difference of climate in the same latitude in the northern hemisphere is in a great measure attributed to the fact of the warm water from the equatorical regions drifting towards the shores of the north of Europe, whilst the cold water from the Arctic regions is constantly flowing southwards along the coast of Labrador, so also the intermediate nature of the climate of Patagonia is doubtless, in some measure, due to the tendency of the cold water of the Antarctic regions to flow northwards through the central parts of the Atlantic Ocean, as pointed out by Maury, thus throwing the warm water southwards along the coasts of Brazil and Patagonia. Argentine Patagonia might, not inaptly, be termed the Sweden, and Chilian Patagonia the Norway of the southern hemisphere. In the north of Patagonia and the southern part of the province of Buenos Ayres the climate, as regards temperature, resembles that of England; and northwards of this is the broadest part of the republic, which contains the city of Mendoza in the far west, and Buenos Ayres in the east, and enjoys one of the finest climates in the world, rivalling that of Southern France and Northern Italy. North of this the summer heat becomes too oppressive, and in the extreme north the climate is thoroughly tropical. In some parts of the northwest the altitude of the country gives it a cooler climate than that of the Chaco in the same latitude. Along the Argentine slopes of the Andes and the adjacent country the climate is remarkable for its dryness, because the prevalent westerly winds lose the moisture which they bring from the Pacific before crossing the mountains. This peculiarity is most marked in the southern part of the continent, where Chilian Patagonia is deluged with almost incessant rain, whilst Argentine Patagonia is dry and arid. In the east, as at Buenos Ayres, there is more rain, which, with southerly winds and occasional north-westerly storms, is often very heavy. The oppressive humidity which is characteristic of the northerly and north easterly winds forms the most disagreeable and unhealthy weather experienced in that part of the country. The climate of Cordova, and also that of some of the more westerly districts, is found very suitable for consumptive patients.

The first Europeans who visited the River Plate were a party of Spanish explorers in search of a south-west passage to the East Indies. Their leader, Juan Dias de Solis, landed, in 1516, with a few attendants on the north coast between Maldonado and Monte Video, where, according to Southey, they were treacherously killed, and then cooked and eaten by the Charrua Indians in sight of their companions on board the vessels. The survivors at once abandoned the country and returned to Spain, reporting the discovery of a fresh-water sea. In 1519 Magalhaens, in the service of the king of Portugal, entered this freshwater sea, or Mar Dulce, as it was then called, but finding no passage to the west, he left it without landing, and then achieved his famous voyage to the East Indies, passing through the strait which bears his name in 1520. After this Sebastian Cabot, already a renowned navigator, who, in the service of Henry VII. of England, had attempted to find a north-west passage to the East Indies, entered the service of Charles I. of Spain, and sailed in command of an expedition fitted out for the purpose of colonising the discoveries of Magalhaens in the East Indies. He, however, entered the River Plate in 1527, and anchored off the present site of the city of Buenos Ayres. He then ascended the Parana, and established a settlement, named San Espiritu, among the Timbù Indians in Santa Fé; and he succeeded in bringing that tribe of Indians to friendly terms with the colony. He continued the ascent of the Parana as far as the cataracts in Missiones, and afterwards explored the Paraguay, from which he entered the Vermejo, where his party suffered severely in a savage fight with the Agaces, or Payaguà Indians. Of this tribe a subdued remnant now lives on the delta of the Pilco-mayo, opposite Asuncion, amalgamating neither with the Spaniards nor with the wild Guaycurus of the surrounding parts of the Chaco. The profusion of silver ornaments worn by these Indians, as well as by the Timbus and Guaranis, led him to give the name of Rio de la Plata, or Silver River, to the splendid stream which he had thus far explored. This name, rendered in English Piver Plate, is now applied only to the estuary below the junction of the Paranâ and Uruguay. One of Cabot’s lieutenants, detached on a separate exploring expedition up the Uruguay, was killed, together with a great part of his crew, by the Charrua Indians. And subsequently at San Espiritu, an attempt of the chief of the Timbus to obtain possession of one of the Spanish ladies in the settlement led to a treacherous massacre of the garrison. Before this latter occurrence Diego Garcia arrived in the river with an expedition fitted out in Spain, for the purpose of continuing the explorations commenced by De Solis; and Cabot returned to Spain, where he applied to Charles I. for the means of opening communications with Peru by way of the Vermejo. But the resources of the king were absorbed in his struggle as emperor (under the name of Charles V.) with Francis I. of France, so that he was obliged to leave the enterprise of South American discoveries to his wealthy nobles. In August 1534 Mendoza left Cadiz for the River Plate at the head of the largest and wealthiest expedition that had ever left Europe for the New World. In January 1535 he entered the River Plate, where he followed the northern shore to San Gabriel, and then crossing the river, he landed on the Pampas. The name of Buenos Ayres was given to the country by Del Campo, who first stepped ashore where the city of that name now stands, and where, on the 2d February, the settlement of Santa Maria de Buenos Ayres was founded; the smaller vessels having been safely harboured in the Riachuelo, half a league south of the settlement. Mendoza’s captains then explored the country between Paraguay and Peru, in which latter country Pizarro had, in 1535, founded the city of Lima. Of one of these expeditions consisting of 200 men, who left Paraguay in February 1537, and are said to have reached the south-east districts of Peru, under Ayolas, every man was killed by the Payaguà Indians in the northern part of the Chaco whilst the expedition was returning laden with plunder. Ayolas had, on his way up the river, built and garrisoned a fort named Corpus Christi among the Timbus in Santa Fé, near the deserted settlement of San Espiritu; and in Paraguay, after three days’ fighting with the Guarani Indians, as narrated by Du Graty, he had, on the 15th August 1536, established a settlement where the city of Asuncion now stands. In the meantime the settlement of Buenos Ayres was attacked and burnt by the Indians; and after terrible sufferings from famine as well as attacks of the Indians, jaguars, and pumas, the Spaniards abandoned the place on the arrival of a fresh expedition from Spain, in company with which they ascended the river, first to Corpus Christi, and then to Asuncion, where, in 1538, Irala was elected captain-general. In 1542 Buenos Ayres was re-established by an expedition sent out from Spain for the purpose under Cabesa de Vaca. This able leader landed at Santa Cathe-rina, in Brazil, and marched overland to Asuncion, from which he sent vessels to join the new expedition at Buenos Ayres, reaching that place, according to Southey, just in time to save the new comers from extermination by the Indians. Here the Spaniards again found themselves unable to withstand the incessant attacks of the savages, and the place was a second time abandoned on the 3d February 1543. At Asuncion the Spaniards were more successful in establishing themselves among the Guarani Indians, who, after much severe fighting, finding themselves unable to vanquish the Spaniards, made alliance with them both offensive and defensive, and also intermarried with them. The events which transpired at Asuncion belong, however, to the history of Paraguay. In 1573 Garay, at the head of an expedition despatched from Asuncion, founded the city of Santa Fé near the abandoned settlements of San Espiritu and Corpus Christi. The expulsion of the Spaniards from the latter place had, according to the Historia Argentina, resulted from a wanton attack made by them on the Caracara Indians, slaughtering the men, and taking the women captive,—a mode of procedure which all Pampa Indians adopted, and have ever since acted on. It is unfortunate, both for the Indians and for the Spaniards, that the bold conquistadores were not always under the guidance of such high principled men as Cabot and Cabesa de Vaca. In 1580, when the new colony had been firmly established, Garay proceeded southwards and made the third attempt to establish Buenos Ayres, under the name “Cuidad de la Santissima Trinidad, Puerto de Santa Maria de Buenos Ayres;” and notwithstanding the determined hostility of the Querandi Indians, who were encouraged by the success of their two preceding wars, the Spaniards succeeded in holding the place. The settlement prospered, and the cattle and horses brought from Europe multiplied and spread over the plains of the Pampas. Whilst the Spaniards of the River Plate were thus engaged, Pizarro had effected the conquest of Peru; and his lieutenant, Almagro, had extended the conquest to the south of Chili, from which, in 1559, Hurtado de Mendoza crossed the Andes, and, having defeated the Araucanian Indians, founded the city of Mendoza. It is interesting to observe, that up to the present day the giant chain of the Andes has been a less effective barrier to trade than the rich plains of the Pampas. This state of affairs will, however, now soon be altered by the railway, for which Mr Clark has just obtained a concession, direct from Buenos Ayres to Mendoza. In 1550 the Spaniards...