Sarface.—The surface of Portugal is for the most part mountainous. Numerous irregular offsets from the great Pyrenean chain enter the two northern provinces of Tres os Montes and Entre Douro e from the Spanish provinces of Asturias and Galicia. One of these offsets extends into the province of Beira, and forming a continuous range takes a southern and western direction, and terminates at Cape Mondego: this is named the Serra de Alcoba. Another mountain range of much greater elevation and extent passes through the central provinces of Beira and Estremadura in a direction from north-north east to south-south-west, and terminates near Lisbon at the Cabo da Roca. This map as it crosses Beira is named the Serra de Estrella; in Fsstretnadura it has several local names, but the main ridge is called the S. rra do Junto. As it approaches its termination it forms a series of ridges running east and west, which occupy the whole space between the Tagus and the sea for a distance of about 30 miles north of Lisbon. Another mountain range crosses the southern end of the kingdom from east to west, separating Algarve from Alemtejo. This range has the names of Serra de Calderfto and Serra de Monchique. It is obviously the continuation of the Sierra Morena of Spain, inter rupted only by the narrow valley of the Gnadiana, and terminates abruptly in the great promontory of Cape St. Vincent.
There are only two plains of great extent in the whole of Portugal, the Campo de Ourique in Alemtejo, and another great plain, partly in Alemtejo and partly in Estremadura, extending south-west and west from the mountains of Portalegre to the eastern bank of the T47.111, along which it is continued northward as far as Abrantes.
Another tract of flat land, but of less extent, in the province of Beira, stretches inland from the scatuary of the river Vouga. The valleys arc very numerous. One of the largest of these forms the river-basin of the Mondego, lying between the Serra de Alcoba and the Serra de Estrella. This valley is exceedingly beautiful and fertile. There are several other fine valleys of less extent, such as those of the Lima and Cevado in Entre Douro e Minho, the upper course of the Vouga in Beira, and the Lis in Estremadura. • Rirers.—The largest of the rivers of Portugal enter it from Spain. The Douro has a western course, and forms the boundary between the two northern provinces and the province of Beira. [Douro.] The Tagus (Tejo) has a course in Portugal at first west, but afterwards south-south-west, and enters the sea below Lisbon. [Thous.] The Guadiana enters from Spain, near Badajoz, and has a southern course partly in Portugal and partly as a boundary-river between the two kingdoms. The Mondego is the largest of the rivers which belong entirely to Portugal. It has numerous affluents, and waters a wide and fertile valley. The Zezere, a deep and rapid river, also entirely within Portugal, rises in the Serra de Estrella, flows along the base of its eastern side, and enters the Tagus below Abrantes. The Sado, or Sad3o, is another large river, with a great number of tribu taries, most of which rise on the northern flank of the Serfs de lionchique, and traverse the great plain of Ourique ; but others flow from the rnountalos south of Evora. The Sado enters the sea at
Setubal. The small. r rivers of Portugal are numerous. The larger rivers, such as the Tagus, the Douro, and others, offer all important inland navigation, which might be extended by canals, of which how ever none have been formed. There are no lakes in the lower lands of Portugal, but there are a few small mountain-lakes. There are salt-marshes in the vicinity of Setubal, and also near Aveiro.
Geology.—Cranite and other eruptive rocks constitute the base of the principal chains and groups of mountains in Portugal. Granite forms the axis of the great mountain range of the Serra de Estrella and Serra do Junto, and shows itself in the lofty peaks of the Serves of Monchique and Calderao. The town of Oporto stands on a masa of granite four or five milts wide, and this rock also forms the base of the neighbouring rocks, but farther to the east sienite takes the place of the granite. These crystalline rocks are very generally flanked and over laid by clay-slates and micaceous 'ciliate, which form the upper strata of the greater part of the provinces of Entre Douro e Minho and Tres os Montag, cover both flanks of the granitic chain of the Serra de Estrella, and extend from the banks of the Zezera to the frontier of Spain. Clay-slates cover the whole of the wine-districts of the Upper Douro, in which all the fine port-wines are produced upon the elates, the line of junction with the granite being the limit of the cultivation of the finer qualities of wine. In the neighbourhood of Valongo, about twelve miles E. from Oporto, a dark-coloured hard roofing slate of the finest quality is extensively quarried for slabs and flags, but not for roofing, tiles being used for that purpose throughout the whole of Portugal. In the same locality are several beds of anthracite coal, which have been long wrought at three or four places, and are much used in the town of Oporto. Primitive limestone shows itself abundantly on the flanks and lower summits of the Selma of Jnnto, Arrabida, Monchique, and Calderio.
Climate, Soil, and Producta—The climate of Portugal is very warm, but no part of the country is subject to the dry and oppressive heats of central Spain. The mean temperature of the year at Coimbra is 82° Fahr., at Lisbon it is 61° 3' Fahr. The inequality of the surface and the extent of coast fronting the Atlantic Ocean occasion great diversities of climate. The more elevated districts arc comparatively cool in winter, and snow falls heavily on the mountains of the two northern provinces. In the southern provinces the winters are very short, snow seldom falls, and the summers are very hot. Rain is abundant on the western coast, especially from October to April. The climate is very healthy in the more elevated districts, hut is less so in the flat lowlands and the vicinity of the salt-marshes.