"In tracing the globe from the pole to the equator we observe a gradation in the complexion nearly in proportion to the latitude of the country, immediately below the arctic circle a high and sanguine colour prevails. From this you descend to the mixture of red and white. Afterwards comes the brown, the blue, the tawny, and at length the black as you proceed to the line. The same distance from the sun, however, does not in any degree indicate the same temperature of climate. Some secondary causes must be taken into consideration, in connecting and limiting its influence. The elevation of the land, its vicinity to the sea, the nature of the soil, the state of cultivation, the course of the winds, and many other circumstances enter into this view. Elevated and mountainous countries are cool in proportion to their altitude above the level of the sea, increasing to the ocean, just in opposite effects, in northern and southern latitudes; for the ocean being of a more equal temperature than the land, in one case corrects the cold, and in the other moderates the heat. Ranges of mountains, such as the Apennines in Italy, and Taurus, Caucasen, and Iman, in Asia, by interrupting the course of cold winds, render the quite dry country below them warmer, and the countries above them colder, than is equivalent to the proportionate difference of latitude. The frigid zone, in Asia, is much wider than it is in Europe; and that continent hardly knows a temperate zone." Climate also receives some difference from the nature of the soil, and some from the degree of cultivation; sand is susceptible of greater heat than clay, and an uncultivated region shaded with forests and covered with undrained marshes, is more frigid in northern and more temperate in southern latitudes, than a country laid open to the direct and constant action of the sun. History informs us that when Germany and Scythia were bound in forests, the Romans often transported their armies across the frozen Danube; but since the civilization of those barbarous regions, the Danube rarely freezes.