HEAT, LIGHT AND BY WIRELESS.

Auckland Star, Volume LXI, Issue 83, 8 April 1930, Page 6

HEAT, LIGHT AND BY WIRELESS.

Marconi, from his yacht in Genoa Harbour, by pressing a button, has set on the liajhts at the radio exhibition at Sydney. The wirej&ss wizard .has long admitted the practicability of power being transmitted over the air. The, Paris correspondent of the London "Daily Majii" recently saw in Germany heating plants actuality operated by wireless waves. The practical and; economical operation of this new discovery is only : .a question of time. We have indeed an example of'such wireless distribution every day of our lives. The heat and light which we receive from tho sun, some 93,000,000 miles away, are really transmitted by wireless waves. When we stand in front of a fire the heat which it emits is conduced by the atmosphere; we do not receive the heajfc.'of the sun in exactly the same way. The air ; which surrounds the earth only extends to a vjery limited distance and cannot act as a direct coriHuctor. In interstellar space there is no atmosphere, and scientists tell us that the temperature of epace is zero, or about 461 degrees below zefro absolute Fahrenheit. How, then, do we receive the heat transmitted by the sun? How do the solar rays penetrate this vast region of intensetoold and yet reach us with a heat which may be sweltering? Clerk-Maxwell, one of the greatest electricians of the age, discovered that light an& electricity travel at exactly the same speed, about 186,000 miles a second. He thus inferred thajfc light was merely an electric vibration of the dfcher. But what is the ether? Scientists confess that they do not know; it ie simply a word for man's ignorance. For all Ave know the ether may" be simply a vacuum. Electric rays can easily pjiss through a vacuum, as Crookes showed by many beautiful experiments. In fact, we see proof oi this every day in the ordinary electric light* bulb, the glowing filament of which works in a vacumm; if air be admitted the lighting power of the filament is soon destroyed. The rays sent out by the sun travel equally in all directions; thus the total body of such wavee, even within the c&rth range, would occupy a sphere 186,000,000 miles in diameter. To supply heat and light uselessly to this vast space would imply a great waste, but there is no such loss in the great scheme of Nature. It is only when these wireless waves reach our atmosphere that they are into heat waves. This is shown by the fact that at a high altitude the air, though nearer the eun, is much colder; but it is much more rarified and therefore cannot absorb the same amount of Jieat. As an indication of the rapidity with which the temperature decreases with altitude, an aeroplane recently ascended at Dayton, Ohio, to a height of nearly 38,000 feet, or about seven miles. At that altitude tho thermometer registered 76 degrees below zero, while on the ground it stood at 71 degrees above zero. This difference of 147 degrees represents- 21 degrees for each mile of altitude. At the same rate, starting with a ground temperature of 32 degrees (freezing point), at an altitude of 23 miles we would reach the astonishing temperature of absolute zero. We have, in fact, leen receiving light, heat and (indirectly) power by wireless from the sun for countless ages. NVhat we look on as a new discovery is merely an eternal process of Nature. The electrical heating; of Paris by means of wireless waves from the Eiffel tower is now engaging the attention of Fremch engineers. Possibly a few years hence a tower of this type will overlook Auckland, affording a magnificent view, while it supplies us with light, heat and power, and serving as an electric beacon to aviators and to ships far out at sea. Such towers, built over coal mines, which would supply the fuel, could radiate power to a vast Electricity, as a science; is advancing with rapid strides, and the range of its practical application is ever widening. —J. 1). LECKIE.