This remarkable uniformity in the climate of Europe is exhibited not only in its temperature, but likewise in the distribution of its rains. The seas washing the shores of Europe supply all parts of it with the necessary amount of moisture. There is no rainless district, nor, with the exception of a portion of the maritime region of the Caspian and a small corner of Spain, any district where droughts occasionally entail the entire loss of the harvest. Rains fall not only regularly every year, but in most countries they occur in every season, the only exception being the countries of the Mediterranean, where autumn and winter are the real rainy seasons. Moreover, in spite of the great diversity in the physical features of Europe, the amount of rain is scarcely anywhere excessive, whether it descends as a fine drizzle, as in Ireland, or in heavy showers, as in Provence and on the southern slope of the Alps. The annual rainfall scarcely ever exceeds thirty-nine inches, except on the flanks of certain mountain ranges which arrest the passage of currents charged with moisture. This uniformity and moderation in the rainfall exercise a regulating influence upon the course of the rivers, for even the smallest amongst them, at all events those to the north of the Pyrenees, the Alps, and the Balkan, flow throughout the year. They rise and fall generally within narrow limits, and inundations on a vast scale are as rare as is want of water for purposes of irrigation. In consequence of this regularity, Europe is able to derive a greater advantage from its waters than other continents where the amount of precipitation is more considerable. The Alps contribute much towards {18} maintaining a regular flow of the rivers; the excess of humidity which falls to their share is stored up in the shape of snow and ice, which descend slowly into the valleys, and melt during the heat of summer. This happens just at a time when the rivers gain least from rain, and lose most by evaporation, and some amongst them would dry up if the ice of the mountains did not come to the aid of the waters descending from the sky. It is thus that a sort of balance is established in the economy of European rivers.