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About The daily Nebraskan. ([Lincoln, Neb.) 1901-current | View Entire Issue (Feb. 14, 1902)
I tv THE DAILY NEBRASKAN. h tunitles for tho inventor here are, therefore, enormous. Tho electro-chemical branches are also very promising. At the present time a large portion of the copper product of tho world Is refined olec trlcally, and practically all tho alum inum which is now used very exten sively In tho arts is produced by electrical processes. There are grow ing up around Niagara Falls a great many workB of this kind which al ready consumo nearly 60,000 horse power, and which will bo increased when more power is provided. Few peoplo outside of tho profession reallzo tho amazing progress that has been made in this field of electro chemistry. And yet wo are only at the beginning. The Inventive genius is producing new processes almost ev ery day that are revolutionizing re sults. Some of the experiments under way are almost fantastic, though they are being pursued by serious minded men. There is one concern, for ex ample, at Niagara that is about to pro duso nitric acid out of air. The air is passed through an electric appa ratus and its component parts, nitro gen and oxygen, which exist as a mere mechanical mixture, are caused to combine chemically. The gases thus produced are absorbed to form a very pure grade of nitric acid, at a low price. So far the process has not been established commercially, but there Is said to bo every prospect of success in tho near future. Then wo shall have tho spectacle of producing, out of the atmosphere, ono of tho most valuable products In the world, for which there Is an unlimited demand for fertilizing purposes. Besides such a process a gold mine would be a cheap and unim portant affair. Hardly a day passes but Bonie new electrical invention is not put out. These inventions vary In importance, some being small devices wnich are used incidentally In various arts, and others being radically new departures which revolutionize some industry, in which case their value may run up to a million dollars or more. Tho possibility of generating elec tricity directly from coal has occupied tho attention of many of tho greatest inventors of the world, Including Mr. Edison, but to tho present time little or no progress has been made. We are still depending upon tho boiler, steam engine and dynamo for nearly all our electric current, except in those fav ored places where nature provides water power, as, for example, at Ni agara and in Switzerland. But most parts of the civilized world do not possess sufficient water power for thoir need. This is particularly true in England, where tho water power is very insignificant. But even with water power tho advantage is not great, as it costs nearly as much to deliver a current in Buffalo from Ni agara as it does to produce it on the spot with a steam engine. What the whole electrical world is looking for is some direct process or apparatus In which coal may be introduced, and from which the electrical current will be generated directly. in other words, something like an electrlca. battery in which coal Is used in the place of zinc. The person who solves this problem on a commercial basis will win greater fame than any in ventor has ever known, and his re- 7 ward In dollars should make him a CroesuB lf-hohas imsinesstalent. The annual Pershing Rifle drill and Bpell-down will take place this afternoon in fche armory. Owing to tho muddy condition of the campus tho usual in spection of the battalion by the governor and his stall: will not be held. W.reless Telegraphy and Hertz Waves Continued from page ). a hollow square as was formed by Na poleon's troops at Waterloo as defense against cavalry. Now conceive tha. such a square has been formed in tin plain and that a wire has been passed nine or ten times around tho Bquare so that finally each grenadier holds In his hands nine turns. In this coil of wire is inserted a strong battery along with a rapid make and break device, called a vibrator. By means 01 an exactly similar squaro surrounded by wiro in tho same way, but provlu ed with a telephono receiver, we may now receive messages across an inter veiling space equal to four times tin diameter of either square. Indeed in 18(J8 Prof. S. 1'. Thompson, pros. dent of tho Englisu Institute of Electrical Engineers, an exceedingly practical man, expressed the opinion that the two systems Just described are botli feasible as a means of connection be- I tween England and America. Ho wan at that time more doubtful aboui l. Marconi system. Wo now come to the Marconi sys tem, and to understand it we must revert to early experiments, whlii have a bearing on the Bubject. Oer sted, in 1820, discovered ie deilectiou of the compass needle, while Arago and Davy ousurved in the samo year the magnetizing properties of a helix. Both eriects show clearly the lact that the electric current and magnetic loice are essentially at right angles to each other, l'erhaps this lact is responsible for tho lack of defi nite mathematical expression of the Interaction ot the two forces prior to the work of Clerk Maxwell. The nexL discoveries involved were those of Michael Faraday, made between 183U and 1835. This prince of experiment ers discovered magneto electric-iuduc tiou or the power which a magnetic field has to set up an electric current in a wire which is moving across it. Ho also discovered the differences In the behavior of various Insulators, as glass, rubber, etc., when they are in terposed between electrified bodies. This Is due to what 'ho called dielec tric inductive capacity and has a strong bearing on Maxwell's electro magnetic theory of light, of which i shall soon speak. Finally Faraday be lieved that there must bo some phys ical relation between light, electricity, and magnetism, ne diligently sought such a relation and thereby discov ered the rotation of the piano of polar ized light when it is projected through a transparent medium undor stress in a magnetic field. Clerk Maxwell bears tho same rela tion to science that Shakespeare bears to literature. Both are almost incon ceivably great. Maxwell, basing hit, work on the experiments which 1 have enumerated, succeeded in combining the magnetic and electric forces in one mathematical expression, which at once completely accounts for them, both In a rational and consistent manner. His theory is really based upon the conception that electric en ergy in tho potential state Is resident In the dielectric or insulator surround ing a charge body, while tho energy of an electric current 1b resident in tire surrounding magnetic Hold. The latter acts very much as if It were endowed with inertia; as though something In the magnetic field, called by Maxwell corpuscles, must be set in rotation like small flywheols before an electric current may he fully es tablished. Some authorities refer, iiccordingly talhe- energy otihe mn& netlc field as being kinetic. Maxwell b theory fully accounts for tho mode and result of tho Interchange of en ergy from tho dielectric to tho mag netic field and vlco versa. When ap plied to light, Maxwell's olectro-mag-netic theory, as above developed, Im plied that thlB form of radiant energy is entirely electrical In Its naturo, bo ing propagated In tho samo manner as an electric current or a magnetic attraction and at the samo flnlto ve locity, namely 185,000 milcB per sec ond. This electromagnetic theory of light was confirmed by tho fact that tho dielectric Inductive capacity, as measured by Faraday, for a given sub stance, was found to be the same as tho refractive Index of tho substance, which Is a necessary consequence of the theory. As regards wireless telegraphy, the significant point in Maxwell's work was that it clearly Implied tho exist ence of electro-magnetic waves in wires or In space, differing In no es BOntlal from light waves except as to length. While light wiivcb are the merest fraction of an Inch, Maxwell showed that waves anywhere from a centimeter to a thousand miles In length were to bo expected. In tho electrical' engineering labor atory Is a machine, an alternator, which produces 125 doublo vibrations in a Bocond. This Is slow compared with the vibrations used by Marconi. A circuit carrying .current which fluctuates no more than 125 times per second will not project energy into space. As the rate of vibration in creabes in the electric circuit, a great er and greater proportion of its en ergy is radiated into spaco never to I return II iniiht have been exnecled that if rapid enough vibration coult have been produced in an electric clr cult enough energy would bto radiutcu to bo appreciable at considerable dis tance. Working upon this hypothesis and in full command of tho Maxwel lian mathematics, a young German philosopher, Henry Hertz, in 188G dis covered tho waves predicted by Max well, and which had been long sought for by experimentalists. Lot us proceed as did Hertz in his famous experiment. Hero is an induc tion coil fed with current through a Wehnelt electrolytic interrupter. By the sound of the interrupter we know that the vibration Is not very rapid since it gives forth only a noise ami not a musical note. But these major sparks in unihon with tho Wehnelt aie each composed of many to and fro impulses occurring at a rate measured in the tens of thousands per second. These are due to what wo would call the natural vibrations of tho coll, and were known before Hertz. Now, a peculiar phenomenon oc curred which gave tho key whoreby tho unexplored region of short waves, i. e., from one half to several meters In length, was to bo unlocked. Hertz, using a piece of wire bent like u let ter "C," the extremities nearly touch ing, discovered that if one end of this wire were applied to one of me dis charge rods of his Induction coil, small subsidiary Bparks would Jump across between the ends of h.a "C ' shaped piece, which ho afterwards named "resonator." To his great mind- this discovery imj it tne electricity had been so suddenly ap plied to one end of the resonator that, although It traveled with the velocity of light, It did not have time to travel around the "C" and arrive at the oth er end, ere a spark hod leaped across from the charged ond to the ono weh had not yet arrived at tho potential ot tha source Hera jniiaL ia & rate of vibration far exceeding tho tons of thousands per second nbovo roforrod to. In fact later dovolopmontq showed that tho spark must bo conBldorod as a socond time differentiated, giving riso to a vibration measured in hun dreds of millions por second. It is this third degree of superimposed vi bration that gives riso to tho bo called Hertz waves, tho samo which are tho actlvo agents In tho Marconi system of signaling. , In view of what has boon said about tho seat of electric and magnoi.e en ergy, It should now bo possible to ex pluin i hat this very rapid vlbnw on . 'hgc1 by the exceedingly rapid tran- Bltion back and forth, of tho energy of the coll. First tho onergy Is magnetic surrounding tho rapidly fiowlng elec tricity of tho spark. When tho vibra tion in this direction ceases, much of tho energy has been Btored quiescent In the dielectric or air surrounding the dlschargo rods, only to How back again nn Instant later Into tho mag netic field with tho revorBo spark. Now conceive that a part of thoso rapid magnetic Impulses radlato In circles concentric with tno spark, changing position only by dint of their ever expanding diameters, Just as circles of water expand wuon a stone Is cast. Tho raun of tnoso mag nolic whirls grow at a rato of 185,000 miles per second, and tho Impulses follow so rapidly ono upon another that the dlstnnco between whirls, or tho wave length, Is ordinarily only a few meters in length. Now Marconi employs a vertical wiro attached to his induction coll. The electric forces vibrating up and down this wire set up a multitude of ever expanding horizontal whirls of magnotlsm, whoso circumferences fin ally cut squarely across tho vertical wire at the receiving station and in duce electric currents therein at rig., angles to tho direction of tho magnetic force. In fact we may conceive that such electric forces are carried along with the magnetic whirl, Btresslng-the ether at right angles to tho plane of tho whirl as it passes. Thus wo have an electric wnve coincident with tne magnetic, their respective planes be ing at right angles to each other. Now it la this electric or vortical wavo which corresponds to what wo mean by a plane, polarized beam of light, although the horlzonal or magnetic wavo Is always present. Hertz waves behave exactly like light waves with two exceptions. They do not affect the retina and they possess tho power of penetrating non-metallic hollies. Waves of a few centimeters in length can penetrate only a limited quantity of earth or stone, but the long waves measured in miles seem to be uble to pass through even hills and moun tains, undiminished in strength. Using largo cylindrical parabolic mirrors made of zinc, Hertz succeeded in dem onstrating tho laws of reflection, re fraction, polarization, interference, etc., and showing their identity to those of light. Like light waves, the Hertz' waves are cut off by metallic bodies even of great thinness. The refractive index for Hertz waves la similar In magnitude to that for or dinary light, and hence largo lenses might bo easily built of glass, pitch, or ; other similar material to condense or focus tho effect from a distant spark upon any particular point. In fact In a system of wirelesB telegraphy there Is no real reason why a multitude of transmitting sparks might not bo singled out and identified at a given receiving station by tho use of proper lenses, even as the stars are differenti ated by a telescope. Pbqf. Geqbqe H. Morse, "Jly l