OCEAN WAVES AS MAN'S WORKMAN.

Oamaru Mail, Volume XXXVI, Issue 10096, 13 March 1909, Page 3 (Supplement)

OCEAN WAVES AS MAN'S WORKMAN.

(By Professor Garrett P. Scrviss.)

Twice a day the ocean along all its coast* rises and falls several feet, and in ■doing so expends an amount ot mechanical energy that is incalculable. Every foot pound of that energy, which inliniiely exceeds in amount the sum total of all the machinery existing in the whole world, is at man's service and disposition, provided only that he can lind out a way to utilise it. If lie could get it all iuirly in his control, the world would be so hill of mechanical energy that machines would take the place ot human muscles, and it would he practically unnecessary for anybody to do any more physical work tlia.ii was"needful for his bodily health. Can he do if' Well, the best answer is, that he is beginning to do it, though on a small scaleas yet, and rather timidly, as ail such things begin. It should be clearly kept in mind that this harnessing of the tides and of -other gigantic lorms of energy which nature places in our reach is not a mere dream of perfectionists, but a practical, •pressing, unrelenting necessity, and one that is recognised by every competent authority. Only the other day the retiring president of the American .Association for the Advancement v of Science, Prclcssur Xichols, of Cornell University, declared : "Saving and thrift offer at best only a. postponement of the day of distress, The end of our supplies of coal and petroleum must ultimately be reached. Hie problem which is presently to confront the race is that of civilised existence without recourse to energy stored by the slow processes of nature. This problem must be solved before the complete exhaustion of our inherited capital." Professor Nichols added that the problem is not without conceivable solution, and he pointed to the enormous energy daily received from the sun, -which, aid we Know how to utilise it without awaiting the slow processes of storage employed by nature, is ample for every thinkable need of the future inhabitants of our planet/' Now, one of the forms 01 solar energyis that represented by the tides, although in. tide production the moon plays even a greater part than the sun, simply on account of her greater nearness to the earth._ Sun and moon together lift billions ot tons of sea water and pour it on our coasts,, placing there -within reach an aggregation of energy greater than that of a million Niagaras, and we supinely regard it and let it go to waste for lack 01 a little ingenuity and a little boldness of initiative. The inventor's road is a hard one, principally because nobody believes in an absolutely new thing, and capital shrinks from risks that are not 011 the old, well-trodden lines. A good many surprising things come from Italy in this progressive age, and among them is an apparatus recently putto work at Rimini to transform the waves of .the sea into a motive'force. With this apparatus the first electric lamp has been made to glow with power derived from the waves. In this case it is not even necessary to wait upon the tides, for in the Adriatic there arc no tides—that sea being too small in area to produce sensible undulations -under the . impulse of the tidal forces of the sun and the moon. But in this case even the winds suffice, keeping the -water in a state of continual undulation, and It is these undulations, which represent enormous energy, that are utilised by Captain Pirandello's apparatus. Go down to Coney Island and watch the combing waves sweeping upon the beach; think of the power that would be needed to arrest them, and then of the possibility which they ; offer of turning that energy into the production of mechanical forces'which would make New York glowlike a city of tlie sun_if that energy were all utilised. Captain I'irandello sets a, mechanically comiected buoy afloat by the shore. That buoy is kept at a constant depth in the water, and, rising;and; falling with the undulations, it transfers to- the related machinery the ceaseless motion of the sea. To guard against the variations in the force and height of the waves, a device is provided for storing up pressed air—compressed by the force oi tlie waves—-and when the water is relativelv calm this stored-np energy is utilised to continue the working of the apparatus. Thus the Adriatic, the seaof romance, is made to put the harness of modern mechanical science on its owii back, and to begin the labor of serving man in a new capacity, the waves of the-ceasek-ss sea lighting" electric lamps in the cities on its shores. This is more than the of tlie Arabian Xights. But other countries than Italy are awok» to this arcat problem. In Kngland Mr William Slice has invented a different apparatus, which as yet is only shown K\\ the form of a working mode!. But itdots its work, and shows -what the system. or one bast'l on similar principles, would ; be capable of with the power of the ocean

behind it. The* incoming water is "passed through a series of, chambers round' a horizontal water wheel, which is thus set in motion. The chambers are so constructed that, whether the water is flowing in one. direction or the other, it always imparts its force to the wheel. 2\ir Snee has the tides in view as the ultimate source of power for driving his apparatus. In this he appeals to the same source of energy as that invoked by a Yankee inventor, .Mr John Hall, jun., of Chicopee. But the~ American has hit upon an entirely different method of application. Pnt in a word, as lie describes his machine, it consists essentially of a hnce tumbler or tank inverted in the water ivhere the tide rises and falls. This inverted tank or chamber is held rigidly in position, so that the undulation of the tide does not vary its level. It stavs rix'ed, and as the water rises within thi m- is driven out at the top. Of course, the air is .under powerful compression, being allo.wed to escape only through a narrow; pipe which conveys it to a compressed air motor, which is thus put into aperation. Like Captain Pirandello's machine, this apparatus also operates independently of the direction of motion of the water. When the tide recedes and the water, consequently, fails in the inverted tank, the air i s "not allowed to re--•nter, and thus a vacuum is formed in the tank. This is -then utilised to run. the motor by regulating the influx of air into the vaccnm through the supply pipe. Liiven a sufficiently rapacious tanlO the Dower thus obtained may' be very great. There, are many places on the coast where the tide rises and falls alternately eight )r ten feet, so that very large reservoirs jf compressed air could" be used. Of L-ourse they must be very strong and stable. To illustrate the operation of 'his nachinc, -Mr J-Jall has constructed a reservoir three feet in depth, which can be ilternateiy filled with water and emptied-: in this reservoir four cider barrels are in- ' verted, having pipes connected at their ;ops, through, which the air escapes as the ivater rises and drives it out, and through ' ivlnch it again enters gradually, when, the falling of the water has ' left the barrels empty of air. With this simple apparatus an air motor of l£-hoi-se-power is operated. A few years ago a tide mill was in jperation near San Francisco in which' a boat moving up and down in a vertical pipe transformed' the energy of the tides into mechanical power. Other similar machines have been tried elsewhere, and always it has been shown that more or less power can thus be obtained. Other forms of tide mills consist of large reservoirs placed beside the beach'and filled by the incoming tide. The reservoir being full, the water, covering several acres, is allowed to flow through raceways, returning, to the sea when the tide is'out. Water wheels or turbines placed in the raceways are driven by the flowing water. Special turbines having a- capacity of 3CO- - have thus bean employed. Another method dispenses with the reservoir and employs large water wheels immersed in a tideway, so that the flow of the water, now in one direction and now in the other, drives the whels. All these are partial solutions of the gre.it and pressing problem to which Professor Xichols referred in his address. All of them really seize upon the power furnished by the sun and tha moon and turn it directly to practical use. In another sense, it is the direct utilisation of the immense force of the earth's rotation en its axis, because but for that rotation there would be no influx of tidal waves upon-'lhe shores. If the earth stood still on its axis, the tide would be an immovable protuberance of the surface of the ocean under the sun and moon —immovable except as it. slowly changed place with the progress of the moon round the earth, and the advance of the earth in its annual journey about the sun. Even then it is conceivable that the change of level of the water might be utilised under certain conditions. The winds, too, would still create a great amount of potential energy, but upon an unrotating earth the system of the winds would diner widely from that which wc now have. The chief problem, at present- is, how to construct such apparatus as that of Pirandello, for instance, on a sufficiently extensive scale. Gravitation solves the problem for us in the case of great waterfalls. We have only to place our turbines under the falling water, and the vast, connected machines begin to hum. driving factories and turning out a thousand necessities of civilised life. The water of the rivers has been 'ifted upon the mountain tops by the sun's heat first transforming the ocean's surface into vapor, which rises and .(lies over the land. Then gravitation brings it back to sea level, and, as it descends, its power is at our disposal. When the sun and the moon lift the tides, gravitation is the primary agent, and the water, instead of going up miles in the air as vapor, ,to be again condensed, simply rises a few feet in the liquid form. But the amount of water thus disturbed in level is indefinitely greater, and the inherent power is greater; only, up to the present, we have hardly done more than fully realise what a boundless source of power is thus thrown at out feet. It seems altogether probable th.it lh-r utilisation of tides and ocean waves will be achieved on a large scale before the direct use of the sun's heat by solar motors Ims been brought about -to any great • extent. Yet both methods will certainly be in use before the end of this century, and we can confidently picture our descendants wondering at our stupidity and our lack of initiative as they dwell upon an earth which no longer has to depend upon the relatively insignificant stores of and petroleum in the rocks for its mechanical energy and its social comforts. That will be an age when man can rest and watch Mature really at work for him. : 6