Science Siftings

New Zealand Tablet, 15 June 1911, Page 1123

Science Siftings

BY ‘VOLT’

Making the Left Hand Work. A good many people never think what a shirker the left hand is. Our two eyes and our two ears and our two feet divide their work equally, or very nearly so, but the left hand only works at what the right hand cannot de alone. In Japan children are trained to use their hands and fingers more carefully than anywhere else in the world. Japanese children can do and make things with their hands that are impossible to American boys and girls, and nearly all of the Japanese, young and old, can draw and write with both hands at once. We could do the same if we had been taught to do so. Carbon Dioxide in the Atmosphere. Every ton of coal, it has been found, which is burnt uses up 300,000 cubic feet of air and renders it unfit for breathing. Suppose that there were no danger of exhausting our coal supply, and that we had enough .to last for ever ; it would only be a few hundred years at our present rate of increase in coal consumption, .and incidentally oxygen consumption, until all the atmosphere on the earth’s surface would be rendered incapable of sustaining life. However, the consumption of coal at present is returning to the atmosphere the carbon dioxide of which it was robbed when the deposits of carbon were stored away in the coal beds during the carboniferous period. The present proportion of carbon dioxide in the air is about one part in 2500. This would be more than doubled, if it were not modified by vegetable life, by the consumption of the present known coal deposits, and it is stated that a doubling of the quantity in the atmosphere would more than double the rate of growth of- plant life. Wireless Communication Between Moving Trains. A railophone installation for wireless inductive telephony 7 and signalling to and from moving trains has been aid down by the Stratford-on-Avon and Midland Junction line from Stratford to Kineton, a distance of ten «r eleven miles. Miss Marie Corelli performed the opening ceremony on April 20. Experiments made show that while a train is running at full speed through this section" conversations can be carried on between the train and the signal-box. The inventor, Mr. Yon. Kramer, claims that the railophone provides instantaneous and full communication, whether running or stationary. It is also possible for two trains on the same line to warn each other automatically of their proximity. The Height of Ocean Waves. • The size claimed for the waves in great ocean storms is often exaggerated, for science has shown that the biggest wave caused by a gale does not exceed 30 feet. Tidal waves have been known to reach heights of 60 feet, but they are an exception. With the increase of size of ocean steamers the point of sight of the passenger has been raised, and it requires the roughest kind of a sea to show a broken horizon from the promenade deck of the newest ocean liners. In these the pitch of the vessel is largely eliminated, although their decks, high above the highest waves of the most severe storms, have been washed by water thrown upward because of the opposition afforded to the advance of a great wave by their hulls. On the decks of the small steamers of past years, where the point of sight was low, the waves often appeared mountainous. Study of Air Currents. Until men began to navigate the air and study its currents and movements little attention was paid to the conditions of the upper atmosphere, and such matters as atmospheric tides and top currents completely encircling the earth were of seemingly little interest. " Since men have flown, and especially since men have flown and fallen, wo have heard a great deal in a vague way of air currents. The moon we know causes the marine tides by its attraction. It draws the water on the surface of the earth toward it in a hump on the side that is exposed to the lunar influence and draws the earth itself away frcm the water on the opposite side, leaving a corresponding hump of water. The air it seems, is affected in the same way. The layer of atmosphere about the earth rises, falls, and flows more freely than water because it is lighter, so the tide comes more quickly in the air at a given spot than the marine tide. This rise and fail, however, means just as much to the_ navigator of the air as the tide in the sea p«es to the sailor and has to accounted for. The most remarkable current, however, is one constant stream in the atmosphere running from west to east completely around the earth in the upper atmosphere.