Spanish geographers have divided the Peninsula into seven distinct chains of mountains. These commence with the Pyrenees and end with the Bætican or Andalucian ranges: these _cordilleras_, or lines of lofty ridges, arise on each side of intervening plains, which once formed the basins of internal lakes, until the accumulated waters, by bursting through the obstructions by which they were dammed up, found a passage to the ocean: the dip or inclination of the country lies from the east towards the west, and, accordingly, the chief rivers which form the drains and principal water-sheds of the greater parts of the surface, flow into the Atlantic: their courses, like the basins through which they pass, lie in a transversal and almost a parallel direction; thus the Duero, the Tagus, the Guadiana, and the Guadalquivir, all flow into their recipient between their distinct chains of mountains. The sources of the supply to these leading arteries arise in the longitudinal range of elevations which descends all through the Peninsula, approaching rather to the eastern than to the western coast, whereby a considerably greater length is obtained by each of these four rivers, when compared to the Ebro, which disembogues in the Mediterranean. The Moorish geographer Alrasi was the first to take difference of climate as the rule of dividing the Peninsula into distinct portions; and modern authorities, carrying out this idea, have drawn an imaginary line, which runs north-east to south-west, thus separating the Peninsula into the northern, or the boreal and temperate, and the southern or the torrid, and subdividing these two into four zones: nor is this division altogether fanciful, for there is no caprice or mistake in tests derived from the vegetable world; manners may make man, but the sun alone modifies the plant: man may be fused down by social appliances into one uniform mass, but the rude elements are not to be civilized, nor can nature be made cosmopolitan, which heaven forfend. [Sidenote: ZONES OF SPAIN.]