AFTER FLYING-WHAT?

New Zealand Herald, Volume XLVI, Issue 14145, 21 August 1909, Page 5 (Supplement)

AFTER FLYING -WHAT?

h ; What the next great invention is likely to be forms the subject of an interesting ' article by G. P. Servi&s in the current num.- *' " ber of Muiisey's Magazine. That the con--i . quest of the air is actually under way cannot be denied, and the question now arises :;->■' —What next? The author says: — ■], During bis last visit to New York, a very . few years ago, the late Lord Kelvin, who '; had lived to see himself accepted as the Nestor of modern science, declared, with all the immense weight of his authority, that human flight, with either dirigible balv 1 loons, or aeroplanes, was unattainable as A practical proposition. Lord Kelvin was '.'■■ marvellously clear-sighted, in -spite of hie eighty years; yet, in this instance, he fail- • "ed to discern what w; obvious to less : gifted intelligences. Even while he spoke .%'-;"" the Wright- brothers veVe actually flying , in Ohio, and Count Zeppelin was perfect- ■ ing his great airship on the shores of the Lake of Constance. . But very few then behoved the stories of what the Wrights ; were doing, and most people smiled pityingly at the German inventor's lumbering .efforts to get his mighty war-bird afloat. Now, kings are eager to fly with the im- ' ; perturbable Ohioans, and the once, dis- ': credited Zeppelin has become the pride and boast of his country, while his aerial levia- • than circles over Germany with squads of ■ . soldiers aboard. European Cabinets are ■ studying the problem of defence against squadrons of invading airships. Engine- ■ builders are considering how they can improve the designs of motors for aeroplanes. .;' '■"'A hundred inventors are, trying to devise- ": new forms of flying machines; and the ecstatic delight expressed by those who '-*'„ have enjoyed the sensation of skimming like a swallow through the air is rapidly :.. developing a craze for flying, which is intensified by recollection of the pleasures of ?„,•• automohiling.

And. to cap all, the meteorologists are : beginning to study the atmosphere from the point of view of the aeronaut. It has long been suspected that the birds know secrets of the air which aid them in their feats of aerostation, and at last exploring ..-.••balloons are revealing some of there se- ? crets. There is talk, at least, of regular:";..'ly .mapping the atmosphere for the bene- . . fit of the featherless birds who are beginning to navigate it. THE NEXT GREAT INVENTION. It is not man's nature to stand still, es- ,, pecially in this age of scientific marvels. ;r Each advance calls immediately for an- :! other;' each acquisition of power helps us toward some further conquest. The field is |r illimitable, and the problems are right at hand. Suppose we look at some of those ,; .problems. : . It is generally agreed that human flight - ; will find its first applications in war and in amusement. The fighters and the plea- /•-. sure-seekers will virtually have the new field to themselves. The great business of the worldtransportation, the exchange ; of products, travel on the large —will not be much affected. The railroads and :V the ocean liners are not threatened with ; serious competition. Exploration will doubtless gain something ; the conquest of the poles, and other hitherto inaccessible parts of the earth, may be facilitated; but the | really pressing needs of humanity do not ' lie in those directions. j What man most urgently wants is increased power over Nature on the surface of the earth. To attain this, he must utilise I energies which now go to waste as far as he §| is concerned. |: Among the greatest of these energies is 1 the flood of radiation that the sun pours j.. over us every day. The solar heat is a f. store of force that comes to us without cost and in unlimited quantity. But its very vastness presents- a difficulty; it is . so widespread that we cannot well grasp it. We take it at second-hand, or at thirdhand. It lifts up clouds of vapour, and spreads them over the mountains, where they condense into water, and as gravitation brings the water down again we seize upon the streams and rivers and : make them drive water-wheels and dynamos. But in all these processes there is .an enormous loss. Why wait for Niagaras? Why not take the energy as it descends direct from the sun? THE VAST POSSIBILITIES OF SON-POWER. Think for a moment what that energy ,; is. On every thirty square feet of surface it is equivalent to one horse-power acting continuously. A space of thirty square feet measures only about five and a-half feet on a side. On a small rug thrown on the ;; ground, then, the sun pours a horse-power ' of energ-v 'A'hich, if we knew how to utilise it, would be continuously at our service as ,-'•', long as the sun was unclouded. Catch the . •k-jlar energy expended on a space one hun- . dred feet square, and you would have three '. hundred and thirty-three horse-power. On , an acre it would amount to more than four- '. teen hundre d horse-power; on a square . mile to nearly a million horse-power.' The ] deck of a steamer at sea receives enough energy from the -sun to drive its engines. It would be discreditable to human genius if no attempt had been made to ■utilise all this force. We have learned to < •fly—good! Now let us learn a still greater , Ml. J I

tiling.. The effort is being made; solar engines already exist, bub they are yet in the stage of the early experiments in flying. The principle of the solar engine is to concentrate the sun's rays, and make them do : (their work at first-hand. There is nothing i new in this, just as there is nothing new in the underlying principle of the airship. Every schoolboy has read of Daedalus and ; Icarus with their wings, and of Archimedes with his burning mirrors. Modern science has just made the dream of Daedalus a reality; it remains to do the same tiling with the hint supplied by the great geometrician of Syracuse, -when, with the aid of the sunbeams, he set fire to the Roman. ',' galleys attacking the port. And the second | achievement promises greater things for humanity than the first.

J;;■_;."■ ." EXPERIMENTAL SOLAR ENGINES. :. Many years ago John Ericsson showed ' now the tiling could be done here in New York. Later, Mouchob, a Frenchman, made a solar engine, which from one hundred square feet of mirrors reflected to a focus enough solar heat to develop one horse-power of energy, which he made available with a boiler. With one hundred square feet of surface there'should have : keen more than three horse-power at his /disposal, but he could utilise only one. Yet • '■the fact that be succeeded so far was pro- * phetic of future achievement. A considerable, advance has been made since the days .of Ericsson and Mouchot, but the magic : 'touch which will make solar motors as common, in all fairly cloudless countries, as "windmills in Holland, is yet to be given. _ One of the greatest of these engines now v 'ii existence is at South Pasadena, in Cali- | where it is employed to pump water , for irrigation. The apparatus is in the shape | of an enormous bottomless dish, thirtyI three and a-half feet in diameter, and comf£ posed of seventeen hundred and eightyheight small mirrors, so arranged that they I all act together in concentrating the sun's rays at a common focus, where is situated feft boiler of one hundred gallons' capacity. £- -The machine is mounted like a telescope, ; to follow the sun as it travels across the <f «ky. The heat at the focus is so great that it, fires a stick of wood just as a match |'is lighted over a burning lamp. A fiexiblo tube conveys the steam from the boiler i to the engine, and the motor develops the . equivalent of ten horse-power, pumping >'ater from a well at the rate of fourteen -" hundred gallons per minute. It is not the ■sun that makes deserts. If "ie solar energy that is poured down upon the Sahara could be set to work pumping f ■■ 'iter from artesian wells, that vast sand- , Baste might be made the great garden of ml&' : ' : - '■ - ■'■ ■'-. '\'\.'.:- ' •'- ~ :;'

VAST POSSIBILITIES OF SUN - POWER.

the world. Even in countries where the sun is clouded part of the time, such motors would be of immense sendee; and, once installed., there would be no expense for fuel, since if the sun is the greatest of monopolists ho charges nothing for his products, or even for their transportation. But the greatest, use for solar motors would be in lands—and there are many such—where no clouds form for four or 'six months in succession. THE MIGHTY TOWER OK THE TIDES. Another vast source of energy which at present' escapes our control is presented by the tides. Twice every day the attraction of the moon and the sun, combined with the rotation of the earth on its axis, causes an up-swelling of the waters of the sea, to pass round the globe. The energy represented by this phenomenon is almost incalculable. It is drawn from the revolution of a fly-wheel eight thousand miles in 'diameter, and weighing six soxtillions of tonsor, in figures, 6,000,000,000.000,000,000,000 tons! That enormous fly-wheel, it is hardly necessary to say, is the earth itself. Stand on the seashore when the tide is coming in, and watch the combing breakers assail the land; or, better still, visit the Bay of Fundy, where, owing to the con- i iiguration of the shores, the tidal wave is narrowed and concentrated, and see the stupendous uplift of the water—reaching a height, in some places, of sixty feet and then reflect on the amount of energy which is thus expended without, benefit, except indirectly, to humanity, but of which, nevertheless, man. might avail himself if he know exactly how to go at it. In comparison with the huge "•bore" tearing its way up the estuary at the head of the Bay of Fundy, or the tremendous tidal waves dashing themselves into foam on the rocks of Maine and New Brunswick, Niagara is hut a baby in force. The friction of the tides, acting through eons of time, has slowed down the rotation of the earth, and tends still to slow it down. Its reaction has driven the moon away from the earth, and is still driving it away, with extreme slowness, but with irresistible power. Even the simple lifting up of the ocean, where the configuration of the shores does not produce bores and driving waves, represents an enormous store } of energy which might be put to the service ( of man. j

Ihese facts have long been known; vet, how little use has been made of the knowledge. Of course there are tide-mills and tide-motors, but. compared with what might be they are as ineffective as the wabbling velocipede that preceded the modern bicycle, or the imitation wings of Lilienthal, which foretold, the soaring"aeroplane of the | Wrights. The power of the tides is, in one respect, like the energy of the sunbeams— is so broadly spread out that man finds it difficult to lay a controlling hand upon it. The problem must be solved more or less indirectly. ( One method is to imprison the water at high tide in reservoirs, and then take advantage of the fall when the tide goes out. One inventor gets round the difficulty, on a small scale, by conducting the water from the rising tide into a reservoir in which are immersed, bottom up, a series of strong hogsheads, connected by flexible tubes with an air-cylinder. When the water rises in the hogsheads it compresses the air within, and drives it into the cylinder. This store of compressed air serves to actuate a motor, and the experimenter has found that the apparatus will work equally well on the recession of the tide, for then the air is drawn in the opposite direction.

Various other ways of storing the force of the tides have been tried, but the capital invention remains to be made. When it comes, it will probably be .associated with the development of electric energy. THE WAVES AND THE WINDS. ■ The waves of the sea, without regard to tidal undulations, are also a possible source of energy. At Rimini, on the shore of the Adriatic, where there is no perceptible tide, an Italian inventor has recently installed an apparatus which utilise*; the ceaseless motion of the waxes to develop an electric current supplying light to a series of streetlamps. Windmills, old as they are, are yet in their childhood, as far as possible development is concerned. Here is another inexhaustible store of energy, due partly to the sun and partly to the rotation of the earth. An English engineer has lately calculated that all the British lighthouses, and many of the coast towns, could be economically lighted by energy derived from windmotors. In England many private lightingplants are run with electricity stored from wind-power. Experience there has shown that the modern wind-motor can be depended upon to work on the average eight hours out of every twenty-four. ' With an average wind velocity of fifteen miles per hour, a ■windmill, twenty-two feet in diameter, making thirty-six revolutions per minute, i produces one horse-power of energy.

This is one of the scources of power on which engineers are counting when the earth's supplies of coal and oil shall have been exhausted. There are broad regions where the wind is practically constant in direction for months, and even throughout the year. In utilising this energy we shall be, to a large extent, drawing upon the force of the same great fly-wheel that furnishes energy in the tides. Is there not something thrilling in the thought of man thus seizing with his puny hands the mighty forces generated by the spinning earth, and submitting them to his will?

Meanwhile, we must be content to grasp what is already within our reach— solar energy, the power of the tides, the force of the winds— without envy, to some future generation the grand discovery that will make this old world new.