current on the African side, and the cold drift on the Australian; and in the South Atlantic, Plato IV. shows that, parallel for parallel, the littoral waters of Brazil are several degrees warmer than those on the African side. Thus at sea the climatic conditions of the land are reversed, for the coldest side of the ocean is next the warmest side of the continent, and vice versa. The winds from extra-tropical seas temper the climates of the shores upon which they blow, not so much by the sensible heat they convey as by the latent heat which is liberated from the vapour they bring. This being condensed, as upon the British Islands and Western Europe, sets free heat enough not only to soften the climate, but to rarefy the air to such an extent as to be observed in the mean barometric pressure.
728. The climates of Europe influenced by the shore-lines of Brazil.—Here we are again tempted to pause and admire the beautiful revelations which, in the benign system of terrestrial adaptations, these researches into the physics of the sea unfold and spread out before us for contemplation. In doing this, we shall have a free pardon from those at least who delight "to look through nature up to nature's God." What two things in nature can be apparently more remote in their physical relations to each other than the climate of 'Western Europe and the profile of a coast-line in South America? Yet this plate reveals to us not only the fact that these relations between the two are most intimate, but makes us acquainted with the arrangements by which such relations are established. The barrier which the South American shore-line opposes to the escape, on the south, of the hot waters from this great equatorial caldron of St. Roque, causes them to flow north, and in September, as the winter approaches, to heat up the western half of the Atlantic Ocean, and to cover it, as far up as the parallel of 40° N., with a mantle of warmth above summer heat. Here heat to temper the winter climate of Western Europe is stored away as in an air-chamber to furnace-heated apartments; and during the winter, when the fire of the solar rays sinks down, the westwardly winds and eastwardly currents are sent to perform their office in this benign arrangement. Though unstable and capricious to us they seem to be, they nevertheless "fulfil His commandments" with regularity and perform their offices with certainty. In tempering the climates of Europe with heat in winter that has been bottled away in the waters of the ocean during summer, these winds and
