Of the Andes which is claimed by Bolivia, and the settlement of the dispute may materially diminish its size.
In 1881 a treaty was signed which provided that the boundary line should follow the highest crests of the Andes forming the watershed as far south as the 52nd parallel,thence east to the 10th meridian and south-east to Cape Dungeness at the eastern entrance to the Straits of Magellan.
Flanking this great widening of the Andes on the south-east are the three short parallel ranges of Cordoba, belonging to another and older formation.
The Argentine part of the great La Plata plain extends from the Pilcomayo south to the Rio Negro, and from the lower terraces of the Andes eastward to the Uruguay and Atlantic. In the north the plain is known as the Gran Chaco, and includes the country between the Pilcomayo and Salado del Norte and an extensive depression immediately north of the latter river, believed to be the undisturbed bottom of the ancient Pampean sea.
The marine facies of the later Tertiaries is confined to the neighbourhood of the coast, and was probably formed after the elevation of the Andes; but inland, freshwater deposits of this period are met with, especially in Patagonia.
During the Tertiary period the great volcanoes of the Andes were formed, and there were smaller eruptions in the Sierras.
(See also Andes.)' Climate.
- The great extent of Argentina in latitude - about 33° - and its range in altitude from sea-level westward to the permanently snow-covered peaks of the Andes, give it a highly diversified climate,, which is further modified by prevailing winds and mountain barriers..
Farther south, in Patagonia, the prevailing wind is westerly, in which case the Andes again " blanket " an extensive region and deprive it of rain, turning it into an arid desolate steppe.
From the mouth of the Colorado to the Andes, ranging from 57° to 55°; but the rainfall increases from 8 in.
The north wind usually terminates with a thunderstorm or with a pampero, a cold south-west wind from the Andes which blows with great violence, causes a fall in temperature of 15° to 20°, and is most frequent from June to November - the southern winter and spring.
The Antarctic beech and Winter's bark (Drimys Winteri) are found at intervals along the Andes to the northern limits of this zone.
On the lower slopes of the Andes are found oak, beech, cedar, Winter's bark, pine (Araucaria imbricata), laurel and calden (Prosopis algarobilla).
Of birds the number of species greatly exceeds that of the mammals, including the rhea of the pampas and condor of the Andes, and the tiny, brilliant-hued humming-birds of the tropical North.
Not only has scientific study advanced at the university of Buenos Aires, but scientific research is promoting the development of the country; examples are the geographical explorations of the Andean frontier, and especially of the Patagonian Andes, by Francisco P. Moreno.
This definition unfortunately ignored the fact that the Andes do not run from north to south in one continuous line, but are separated into cordilleras with valleys between them, and covering in their total breadth a considerable extent of country.
In the western hemisphere they range along the Mexican highlands and the Andes far into the tropics, while in the Old World the genus, well represented in the Himalayas and the hills of China, exists likewise in the peninsula of Malacca, in the Indian Archipelago and Malaya to the Philippine Islands and Borneo.
In the interior of South America the Spanish conquerors had explored the region of the Andes from the isthmus of Panama to Chile.
Pedro de Valdivia in 1540 made an expedition into the country of the Araucanian Indians of Chile, and was the first to explore the eastern base of the Andes in what is now Argentine Patagonia.
In 1541 Francisco de Orellana discovered the whole course of the Amazon from its source in the Andes to the Atlantic. A second voyage on the Amazon was made in 1561 by the mad pirate Lope de Aguirre; but it was not until 1639 that a full account was written of the great river by Father Cristoval de Acufia, who ascended it from its mouth and reached the city of Quito.
Lofty lines of fold mountains form the " backbones " of North America in the Rocky of Mountains and the west coast systems, of South America in the Cordillera of the Andes, of Europe in the Pyrenees, Alps, Carpathians and Caucasus, and of Asia in the mountains of Asia Minor, converging on the Pamirs and diverging thence in the Himalaya and the vast mountain systems of central and eastern Asia.
Naturally the company named does not reach all of these points, but its line across the Andes supplies the indispensable link of communication, in the absence of which the east coast towns and the west coast towns have hitherto been as widely separated as if they had been located on different continents-indeed, far more widely separated in point of time and of freight charges than Great Britain and the United States.
South of the Negro the country is arid, barren and lies in great shingle-covered terraces sloping eastward to the Atlantic; its larger part is practically uninhabitable, only the river valleys and the foot-hills of the Andes having a regular water supply.
The ship to which he was appointed was ordered to China, and he found opportunities during the voyage for indulging his passion for exploration, making a journey from Rio de Janeiro to the base of the Andes, and another from Bombay through India to Ceylon.
Sir Martin Conway's "Map of the Andes of La Paz" (1: 600,000; 'goo) as well as Major P. H.
This decline in its prosperity was checked, and the modern development of the port began, when a railway was built from Callao into the heart of the Andes, and Callao is now an important factor in the development of copper-mining.
America its natural occurrence appears to be limited to west of the Andes, but the tree is abundant in Mexico, Guatemala and Nicaragua.
America down to the slopes of Chimborazo; the Cordilleras of the Andes separating the Castilloas from the Heveas of Brazil.
There are winter winds from the Andes, but in the summer season there are cold currents of air from up-river (ventos da cima) which are usually followed by downpours of rain.
The tapir also has an extensive range between the coast and the foothills of the Andes, and from northern Argentina to south-eastern Colombia.
The latter region is densely forested from the Atlantic to the Andes, but with a varying width of about 200 m.
A' branch of the eastern chain of the Andes enters Venezuela in the west about 7° N.
Beyond the Cojedes begin two parallel ranges known as the Maritime Andes of Venezuela, which stretch east and west along the coast.
Behind the wide bay between Cape Codera and Cumana there is an interruption in the Maritime Andes; but both ranges reappear between Cumana and the Gulf of Paria.
West of the Maritime Andes low ranges (3500-5000 ft.) trend northwards from the end of the Sierra de Merida towards the coast on the east side of the Lake of Maracaibo, while the region on the west of that lake consists of lagoon-studded lowlands.
Along the Brazilian frontier and about the sources of the Orinoco tributaries on the eastern slops of the Andes there are extensive forests, sometimes broken with grassy campos.
Of Maracaibo among a large number of lakes, lagoons and swamps; Valencia, near the city of that name, in the Maritime Andes, about 1350 ft.
These ranges appear to belong to two systems. The Cordillera of Merida is one of the branches of the Andes, and the strike of the folds which compose it is usually from south-west to north-east.
In the Maritime Andes at and above the altitude of Caracas it may be described as semitropical, and in the still higher regions of western Venezuela it approaches the mild temperate.
On the coast and the northern slopes of the Maritime Andes the tropical heat is greatly modified by the trade-winds.
Irrigation, which has not been used to any great extent, is needed in some parts of the country for the best results, but in others, as in the valleys and on the northern slopes of the Maritime Andes, the rainfall is sufficiently well distributed to meet most requirements.
CHINCHILLA, a small grey hopping rodent mammal (Chinchilla lanigera), of the approximate size of a squirrel, inhabiting the eastern slopes of the Andes in Chile and Bolivia, at altitudes between 8000 and 12,000 ft.
Chinchillas live in burrows, and these subterranean dwellings undermine the ground in some parts of the Chilean Andes to such an extent as to cause danger to travellers on horseback.
The Peruvian chinchilla (C, brevicaudata) is larger, with relatively shorter ears and tail; while still larger species constitute the genus Lagidium, ranging from the Andes to Patagonia, and distinguished by having four in place of five front-toes, more pointed ears, and a somewhat differently formed skull.
Among them may be mentioned the aperea or restless cavy (C. porcellus or C. aperea) of Brazil; the Bolivian C. boliviensis, found at great elevations in the Andes; the Brazilian rock-cavy (C. rupestris), characterized by its short blunt claws; and the Peruvian C. cutleri.
JALAP, a cathartic drug consisting of the tuberous roots of Ipomaea Purga, a convolvulaceous plant growing on the eastern declivities of the Mexican Andes at an elevation of 5000 to 8000 ft.
The sierra is the region of the Andes, and is about 250 m.
Half of these have their origin in the summits of the Andes, and run with a permanent supply of water into the ocean.
The absence of rain here is ascribed to the action of the lofty uplands of the Andes on the trade-wind, and to the influence of the cold Humboldt current sweeping northward along the west coast of the continent.
When the wind rises above the snow-capped Andes, the last particle of moisture is wrung from it that a very low temperature can extract.