Part 8

The coast of Chile is fringed with an extraordinary number of islands extending from Chiloé S. to Cape Horn, the grouping of which shows that they are in part the summits of a submerged mountain chain, a continuation southward of the Cordillera Maritima. Three groups of these islands, called the Chiloé, Guaytecas and Chonos archipelagoes, lie N. of the Taytao peninsula (lat. 45° 50' to 46° 55' S.), and with the mainland to the E. form the province of Chiloé. The largest of these is the island of Chiloé, which is inhabited. Some of the smaller islands of these groups are also inhabited, though the excessive rainfall of these latitudes and the violent westerly storms render them highly unfavourable for human occupation. Some of the smallest islands are barren rocks, but the majority of them are covered with forests. These archipelagoes are separated from the mainland in the north by the gulfs of Chacao (or Ancud) and Corcovado, 30 to 35 m. wide, which appear to be a submerged part of the great central valley of Chile, and farther south by the narrower Moraleda channel, which terminates southward in a confusing network of passages between the mainland and the islands of the Chonos group. One of the narrow parts of the Chilean mainland is to be found opposite the upper islands of this group, where the accidental juxtaposition of Magdalena island, which indents the continent over half a degree at this point, and the basin of Lake Fontana, which gives the Argentine boundary a sharp wedge-shaped projection westward, narrows the distance between the two to about 26 m. The Taytao peninsula, incorrectly called the Tres Montes on some maps, is a westward projection of the mainland, with which it is connected by the narrow isthmus of Ofqui, over which the natives and early missionaries were accustomed to carry their boats between the Moraleda Channel and Gulf of Peñas. A short ship canal here would give an uninterrupted and protected inside passage from Chacao Channel all the way to the Straits of Magellan, a distance of over 760 m. A southern incurving projection of the outer shore-line of this peninsula is known as Tres Montes peninsula, the most southern point of which is a cape of the same name. Below the Taytao peninsula is the broad open Gulf of Peñas, which carries the coast-line eastward fully 100 m. and is noticeably free from islands. The northern entrance to Messier Channel is through this gulf. Messier, Pitt, Sarmiento and Smyth's Channels, which form a comparatively safe and remarkably picturesque inside route for small steamers, about 338 m. in length, separate another series of archipelagoes from the mainland. These channels are in places narrow and tortuous. Among the islands which thickly fringe this part of the coast, the largest are Azopardo (lying within Baker Inlet), Prince Henry, Campaña, Little Wellington, Great Wellington and Mornington (of the Wellington archipelago), Madre de Dios, Duke of York, Chatham, Hanover, Cambridge, Contreras, Rennell and the Queen Adelaide group of small barren rocks and islands lying immediately north of the Pacific entrance to the Straits of Magellan. The large number of English names on this coast is due to the fact that the earliest detailed survey of this region was made by English naval officers; the charts prepared from their surveys are still in use and form the basis of all subsequent maps. None of these islands is inhabited, although some of them are of large size, the largest (Great Wellington) being about 100 m. long. It has likewise been determined, since the boundary dispute with Argentina called attention to these territories and led to their careful exploration at the points in dispute, that Skyring Water, in lat. 53° S., opens westward into the Gulf of Xaultegua, which transforms Ponsonby Land and Cordoba (or Croker) peninsula into an island, to which the name of Riesco has been given. The existence of such a channel was considered probable when these inland waters were first explored in 1829 by Captain FitzRoy, but it was not discovered and surveyed until three-quarters of a century had elapsed. Belonging to the Fuegian group south of the Straits of Magellan are Desolation, Santa Ines, Clarence, Dawson, Londonderry, Hoste, Navarin and Wollaston islands, with innumerable smaller islands and rocks fringing their shores and filling the channels between them. Admirable descriptions of this inhospitable region, the farthest south of the inhabited parts of the globe, may be found in the _Narrative of the Surveying Voyages of His Majesty's Ships "Adventure" and "Beagle" between the years 1826 and 1836_ (3 vols., 1839).

The western and larger part of Tierra del Fuego (q.v.) belongs to Chile. About 63 m. S.W. of Cape Horn, in lat. 56° 25' S., is the Diego Ramirez group of small, rocky islands, the most southern possession of the republic. Its westernmost possessions are Sala-y-Gomez and Easter islands, the former in about 27° S., 105° W., and the latter, the easternmost inhabited Polynesian island, in 27° 6' S., 109° 17' W. Much nearer the Chilean coast (396 m.), lying between the 33rd and 34th parallels, are the three islands of the Juan Fernandez group, and rising apparently from the same submerged plateau about 500 m. farther north of the latter are the rocky islets of San Ambrosio and San Felix, all belonging to Chile. North of Chiloé there are few islands in close proximity to the coast. The more important of these are La Mocha, off the southern coast of Arauco, in lat. 38° 20' S., which is 8 m. long and rises to an elevation of 1240 ft. above the sea; Santa Maria, 30 m. south-west of Concepcion, which partially encloses the Bay of Arauco and is well cultivated; and Quiriquina, lying off the port of Talcahuano in the entrance to Concepción bay. There are a few barren islands on the desert coast, the largest of which are between Coquimbo and Caldera. Since the removal of their guano deposits they have become practically worthless, except where they serve to shelter anchorages.

Harbours.

The coast of northern and central Chile is singularly deficient in good harbours. Those of the desert region are only slight indentations in a remarkably uniform coast-line, sheltered on one side by a point of land, or small island. The landings are generally dangerous because of the surf, and the anchorages are unsafe from storms on the unprotected side. Among the most frequented of these are Valparaiso, Coquimbo, Caldera, Iquique and Arica. There are some small harbours for coasting vessels of light draught along the coast of central Chile, usually at the partially obstructed mouths of the larger rivers, as San Antonio near the mouth of the Maipó, Constitución at the mouth of the Maule, and Llico on the outlet of Lake Vichuquen, but there is no harbour of importance until Conceptión (or Talcahuano) Bay is reached. There are three harbours on this bay, El Tomé, Penco and Talcahuano (q.v.), the last being the largest and best-protected port on the inhabited part of the Chilean coast. Immediately south of this bay is the large Bay of Arauco, into which the Bio-Bio river discharges, and on which, sheltered by the island of Santa Maria, are the ports of Coronel and Lota. The next important harbour is that of El Corral, at the mouth of the Valdivia river and 15 m. below the city of Valdivia. The Bay of San Carlos on the northern coast of Chiloé, which opens upon the narrow Chacao channel, has the port of Ancud, or San Carlos, and is rated an excellent harbour for vessels of light and medium draught. Inside the island of Chiloé the large gulfs of Chacao (or Ancud) and Corcovado are well protected from the severe westerly storms of these latitudes, but they are little used because the approach through the Chacao channel is tortuous and only 2 to 3 m. wide, and the two gulfs, though over 30 m. wide and 150 m. long, are beset with small rocky islands. At the north end of the first is the Reloncavi, a large and nearly landlocked bay, on which stands Puerto Montt, the southern terminus of the Chilean central railway. The large Gulf of Peñas, south of Taytao peninsula, is open to the westerly storms of the Pacific, but it affords entrance to several natural harbours. Among these are the Gulfs of Tres Montes and San Estevan, and Tarn Bay at the entrance to Messier Channel. The next 300 m. of the Chilean coast contain numerous bays and inlets affording safe harbours, but the mainland and islands are uninhabited and the climate inhospitable. Behind Rennell Island in lat. 52° S., however, is a succession of navigable estuaries which penetrate inland nearly to the Argentine frontier. The central part of this group of estuaries is called Worsley Sound, and the last and farthest inland of its arms is Last Hope Inlet (Ultima Esperanza), on which is situated the Chilean agricultural colony of Puerto Consuelo. The Straits of Magellan, about 360 m. in length, lie wholly within Chilean territory. Midway of them is situated Punta Arenas, the most southern town and port of the republic.

Rivers.

Except in the extreme south the hydrography of Chile is of the simplest description, all the larger rivers having their sources in the Andes and flowing westward to the Pacific. Their courses are necessarily short, and only a few have navigable channels, the aggregate length of which is only 705 m. Nearly all rivers in the desert region are lost in the sands long before reaching the coast. Their waterless channels are interesting, however, as evidence of a time when climatological conditions on this coast were different. The principal rivers of this region are Sama (which forms the provisional boundary line with Peru), Tacna, Camarones, Loa, Copiapó, Huasco, Elqui, Limari and Choapa. The Loa is the largest, having its sources on the slopes of the Cordillera south of the Minho volcano, between 21° and 21° 30' S. lat., and flowing south on an elevated plateau to Chiuchiu, and thence west and north in a great curve to Quillaga, whence its dry channel turns westward again and reaches the Pacific in lat. 21° 28' S., a few miles south of the small port of Huanillos. Its total length is estimated at 250 m. The upper courses of the river are at a considerable elevation above the sea and receive a large volume of water from the Cordilleras. The water of its upper course and tributaries is sweet, and is conducted across the desert in pipes to some of the coast towns, but in its lower course, as in all the rivers of this region, it becomes brackish. The Copiapó, which once discharged into the sea, is now practically exhausted in irrigating a small fertile valley in which stands the city of that name. The Copiapó and Huasco have comparatively short courses, but they receive a considerable volume of water from the higher sierras. The latter is also used to irrigate a small, cultivated valley. The rivers of the province of Coquimbo--the Elqui or Coquimbo, Limari and Choapa--exist under less arid conditions, and like those of the province of Aconcagua--the Ligua and Aconcagua--are used to irrigate a much larger area of cultivated territory. The central agricultural provinces are traversed by several important rivers, all of them rising on the western slopes of the snow-clad Andes and breaking through the lower coast range to the Pacific after being extensively used to irrigate the great central valley of Chile. These are the Maipó (Maypó or Maipú), Rapel, Mataquito, Maule, Itata, Bio-Bio, Imperial, Tolten, Valdivia or Calle-Calle, Bueno and Maullin. With the exception of the first three, these rivers have short navigable channels, but they are open only to vessels of light draught because of sand-bars at their mouths. The largest is the Bio-Bio, which has a total length of 220 m., 100 of which are navigable. These rivers have been of great service in the agricultural development of this part of Chile, affording means of transportation where railways and highways were entirely lacking. Some of the larger tributaries of these rivers, whose economic value has been equally great, are the Mapocho, which flows through Santiago and enters the Maipó from the north; the turbulent Cachapoal, which joins the Rapel from the north; the Claro, which waters an extensive part of the province of Talca and enters the Maule from the north; the Ñuble, which rises in the higher Andes north of the peaks of Chillan and flows entirely across the province of Ñuble to join the Itata on its western frontier; the Laja, which rises in a lake of the same name near the Argentine frontier in about lat. 35° 30' S. and flows almost due west to the Bio-Bio; and the Cautin, which rises in the north-east corner of Cautin and after a tortuous course westward nearly across that province forms the principal confluent of the Imperial. The unsettled southern regions of Chiloé (mainland) and Magallanes are traversed by a number of important rivers which have been only partially explored. They have their sources in the Andes, some of them on the eastern side of the line of highest summits. The Puelo has its origin in a lake of the same name in Argentine territory, and flows north-west through the Cordilleras into an estuary (Reloncavi Inlet) of the Gulf of Reloncavi at the northern end of the Gulf of Chacao. Its lower course is impeded in such a manner as to form three small lakes, called Superior, Inferior and Taguatagua. A large northern tributary of the Puelo, the Manso, has its sources in Lake Mascardi and other lakes and streams south-east of the Cerro Tronador, also in Argentina, and flows south-west through the Cordilleras to unite with the Puelo a few miles west of the 72nd meridian. The Reloncavi Inlet also receives the outflow of Lake Todos los Santos through a short tortuous stream called the Petrohue. The Comau Inlet and river form the boundary line between the provinces of Llanquihue and Chiloé, and traverse a densely wooded country in a north-westerly direction from the Andes to the north-eastern shore of the Gulf of Chacao. Continuing southward, the Yelcho is the next important river to traverse this region. It drains a large area of Argentine territory, where it is called the Rio Fetaleufu or Fetalauquen, its principal source being a large lake of the same name. It flows south-west through the Andes, and then north-west through Lake Yelcho to the Gulf of Corcovado. The Argentine colony of the 16th of October, settled principally by Welshmen from Chubut, is located on some of the upper tributaries of this river, in about lat. 43° S. The Palena is another river of the same character, having its source in a large frontier lake called General Paz and flowing for some distance through Argentine territory before crossing into Chile. It receives one large tributary from the south, the Roo Pico, and enters an estuary of the Gulf of Corcovado a little north of the 44th parallel. The Frias is wholly a Chilean river, draining an extensive Andean region between the 44th and 45th parallels and discharging into the Puyuguapi channel, which separates Magdalena island from the mainland. The Aisen also has its source in Argentine territory near the 46th parallel, and drains a mountainous region as far north as the 45th parallel, receiving numerous tributaries, and discharging a large volume of water into the Moraleda channel in about lat. 45° 20' S. The lower course of this river is essentially an inlet, and is navigable for a short distance. The next large river is the Las Heras, or Baker, through which the waters of Lakes Buenos Aires and Pueyrredon, or Cochrane, find their way to the Pacific. Both of these large lakes are crossed by the boundary line. The Las Heras discharges into Martinez Inlet, the northern part of a large estuary called Baker or Calen Inlet which penetrates the mainland about 75 m. and opens into Tarn Bay at the south-east corner of the Gulf of Peñas. Azopardo (or Merino Jarpa) island lies wholly within this great estuary, while at its mouth lies a group of smaller islands, called Baker Islands, which separate it from Messier Channel. The course of the Las Heras from Lake Buenos Aires is south and south-west, the short range of mountains in which are found the Cerros San Valentin and Arenales forcing it southward for an outlet. Baker Inlet also receives the waters of still another large Argentine-Chilean lake, San Martin, whose far-reaching fjord-like arms extend from lat. 49° 10' to 48° 20' S.; its north-west arm drains into the Tero, or La Pascua, river. Lake San Martin lies in a crooked deeply cut passage through the Andes, and the divide between its southern extremity (Laguna Tar) and Lake Viedma, which discharges through the Santa Cruz river into the Atlantic, is so slight as to warrant the hypothesis that this was once a strait between the two oceans. After a short north-westerly course the Toro discharges into Baker Inlet in lat. 48° 15' S., long. 73° 24' W. South of the Toro there are no large rivers on this coast, but the narrow fjords penetrate deeply into the mountains and bring away the drainage of their snow-capped, storm-swept elevations. A peculiar network of fjords and connecting channels terminating inland in a peculiarly shaped body of water with long, widely branching arms, called Worsley Sound, Obstruction Sound and Last Hope Inlet, covers an extensive area between the 51st and 53rd parallels, and extends nearly to the Argentine frontier. It has the characteristics of a tidewater river and drains an extensive region. The sources of the Argentine river Coile are to be found among the lakes and streams of this same region, within Chilean territory. A noteworthy peculiarity of southern Chile, from the Taytao peninsula (about 46° 50' S. lat.) to Tierra del Fuego, is the large number of glaciers formed on the western and southern slopes of the Cordilleras and other high elevations, which discharge direct into these deeply cut estuaries. Some of the larger lakes of the Andes have glaciers discharging into them. The formation of these icy streams at comparatively low levels, with their discharge direct into tidewater estuaries, is a phenomenon not to be found elsewhere in the same latitudes.

Lakes.

The lakes of Chile are numerous and important, but they are found chiefly in the southern half of the republic. In the north the only lakes are large lagoons, or morasses, on the upper saline plateaus between the 23rd and 28th parallels. They are fed from the melting snows and periodical storms of the higher Andes, and most of them are completely dry part of the year. Their waters are saturated with saline compounds, which in some cases have considerable commercial value. In central Chile above the Bio-Bio river the lakes are small and have no special geographical interest, with the exception perhaps of the Laguna del Maule, in 36° 7' S., and Laguna de la Laja, in 37° 20', which lie in the Andes near the Argentine frontier and are sources of the two rivers of the same names. Below the Bio-Bio river there is a line of large picturesque lakes extending from the province of Cautin, south through that of Llanquihue, corresponding in character and position to the dry lacustrine depressions extending northward in the same valley. They lie on the eastern side near the Cordilleras, and serve the purpose of great reservoirs for the excessive precipitation of rain and snow on their western slopes. With one exception they all drain westward into the Pacific through short and partly navigable rivers, and some of the lakes are also utilized for steamship navigation. These lakes are Villarica on the southern frontier of Cautin, Rinihue and Ranco in Valdivia, and Puyehue, Rupanco, Llanquihue and Todos los Santos in Llanquihue. The largest of the number are Lakes Ranco and Llanquihue, the former with an estimated area of 200 sq. m. and the latter of 300 sq. m. Lake Todos los Santos is situated well within the Andean foothills north-east of Puerto Montt and at an elevation of 509 ft., considerably above that of the other lakes, Lake Ranco being 230 ft. above sea-level. The great Andean lakes of General Paz (near the 44th parallel), Buenos Aires (in lat. 46° 30' S.), Pueyrredon, or Cpchrane (47° 15' S.) and San Martin (49° S.), lie partly within Chilean territory. In the extreme south are Lagoa Blanca, a large fresh-water lake in lat. 52° 30' S., and two large inland salt-water sounds, or lagoons, called Otway Water and Skyring Water, connected by FitzRoy Passage.

_Geology._--Chile may be divided longitudinally into two regions which differ from each other in their geological structure. Along the coast lies a belt of granite and schist overlaid unconformably by Cretaceous and Tertiary deposits; inland the mountains are formed chiefly of folded Mesozoic beds, together with volcanic rocks of later date. The great longitudinal valley of Chile runs approximately, but only approximately, along the boundary between the two zones. Towards the north the coastal zone disappears beneath the sea and the Andean zone reaches to the shore. The ancient rocks which form the most characteristic feature of the former do indeed occur upon the coast of Peru, but in the north of Chile they are found only in isolated masses standing close to the shore or, as at Mejillones, projecting into the sea. South of Antofagasta the old rocks form a nearly continuous band along the coast, extending as far as Cape Horn and Staten Island, and occupying the greater part of the islands of southern Chile. Lithologically they are crystalline schists, together with granite, diorite, gabbro and other igneous rocks. They are known to be pre-Jurassic, but whether they are Palaeozoic or Archaean is uncertain. They are strongly folded and are overlaid unconformably by Cretaceous and Tertiary deposits. In the north both the Cretaceous and Tertiary beds of this zone are limited in extent, but towards the south Mesozoic beds, which are at least in part Cretaceous, form a band of considerable width. The Tertiary beds include both marine and terrestrial deposits, and appear to be chiefly of Miocene and Pliocene age. The whole of the north part of Tierra del Fuego is occupied by plateaus of horizontal Tertiary strata.