THE WIND

Evening Star, Issue 21090, 30 April 1932, Page 5

THE WIND

“ How the wind howls!”- says somebody. . “What a high wind!” says someWhat a refreshing sea breeze !”- says somebody. “What is the wind and where does it come from?” asks somebody. The wind is air. When the wind blows, it is the air rushing this way or Our earth is surrounded, encased, all over with a covering of air._ Just in the same way as an orange is covered with peel or a peach is covered with down.. This covering of air is _ fortyfive to fifty miles deep, and if you could—which you can’t—get on the top of it and look through the air to the earth, you would see us mortals walking about at the bottom. It would bo much the same as looking at the stones and shells that lie at the bottom of the sea. . There are two things that make tne air move about—make the wind blow, in fact. , ~ One is that the earth goes whirling round at a terrific rate all the time. Try spinning a big top and you can feel the wind blowing round it as it spins. ~ , , The other thing which makes the wind blow is that some parts of earth get warm with the sun. ihe warm earth heats the air above it. Warm air is always lighter than cold air and flies away upwards like a coloured air balloon does if you let the string go. As the warmed air goes up towards the sky, the cold air which has been lying on the sea or on a colder piece of the earth, rushes in to fill up the place which the hot air has left, and .then we say “ the wind is blowing ” or "what a delicious breeze.” This is particularly noticeable in the West Indian Islands which lie near the Equator, which is the hottest place in the world. Early in the morning the sun begins to shine on these islands and the warm air begins to go upwards. Then the air that has lain all night upon the cool sea around the islands begins to flow in on to the land and a “ soft sea breeze ” spings up. As the morning advances the land becomes hotter and hotter, and the hot air goes up quicker and quicker, and the cool air from the sea comes in faster and faster till it is “ a stiff breeze.” As the snn goes down the land cools and the air only rises slowly and the cool air • blows in equally slowly. By sunset the wind has dropped altogether. The land begins to cool, and now the sea is warmer than the land. The warm air over the sea takes a turn at going up, and the cooler air from the land rushes out over the sea. The “ wind lias changed,’’ and now it blows off the land on to the sea! Then the morning comes again with its .“iinshine, the wind changes, and it begins all over again! The wind is like a train and moves along at a certain rate of so many miles an hour.

Sailors are obliged to take much more notice of the rate the wind is blowing than a landsman does. The sailor has divided the wind into twelve divisions, beginning with “faint air” and finishing up with “ storm.” The sailor is taught just how much sail should he used for each division of wind.

If the wind is travelling at 7 miles an hour, it is a gentle air; 14 miles, a light breeze; 21 miles, a good steady breeze; 40 miles, a gale ;_ 00 miles, a heavy storm; and anything from 80 to 1,50 miles an hour is a hurricane,

Even a hurricane has its wonderful uses! In times of great calm and stillness of the air, germs of disease and poison begin to flourish. So when wo hear the wind howling and roaring round the corners and alleys, wo can remember that it is one of God’s great Sanitary Engines and is cleaning the world around us.