Page:Popular Science Monthly Volume 7.djvu/502

486, in Britain, for instance, we fall within the sway of the south-rushing polar current deflected to the east by the earth's rotation, and sometimes within that of the north-rushing current from the equator, deflected to the west by the rotation which it shared with the earth at the zone from which it started. In Britain this southwest wind comes to us laden with vapor from the great mass of the Atlantic, and makes Ireland and our western shores unusually damp and rainy. The relative temperatures of sea and land in the temperate zones are continually changing with the seasons. In summer and autumn the Atlantic is colder than the European Continent, and this has a tendency to produce a west current at the surface. In winter and spring the Atlantic is warmer than the continent, and this has a tendency to produce an east wind. Sometimes one of these varying tendencies gains the predominance and sometimes another, and the result is constant and often rapid change and variety. The heat and moisture which the wind brings with it depend entirely upon where it comes from, and what it has passed in its way. A west wind blows to us from the Atlantic, and usually brings rain; an east wind brings up the fog of the German Ocean; and in winter and spring the prevalent northeaster brings the cold and often the snow of Russia and Norway. At the sea-side, unless it be overpowered by a general current, there is a breeze from off the sea during the day, and a breeze from off the land during the night. The quantity of rain that falls in this zone at different points is extremely variable, and depends upon the position of a place with regard to mountain-masses and the seas from which the vapors come. In England the rainfall is greatest on the west side of the island, and smallest on the east. The difference within a short distance is sometimes very striking. There are 140 inches a year at Borrowdale, in the lake district, and not more than 20 inches at Shields and Sunderland, which are directly opposite on the east coast. But the habitual humidity of the atmosphere often varies but little between places the rainfall of which is very different. The number of days upon which more or less rain falls, varies in England from 100 to 300, but in the Mediterranean region the number of days is fewer, the quantity is smaller, and there is an almost regular period of entirely dry weather in summer. Taking the north temperate zone as a whole, there is, as a rule, least rain in places away from hills in the interior of continents, and most in insular and mountainous situations.—Gardener's Chronicle.