TESTING THE ELECTRIC "WITCH."

New Zealand Herald, Volume XVIII, Issue 6147, 30 July 1881, Page 7

TESTING THE ELECTRIC "WITCH."

Mb. Thomas Peacock, President of the Auckland Institute, writes as follows:— On a recent occasion, in my address to tho Auckland Institute, I remarked upon the desideratum of being able to store up electlicity for future use, and referred to the secondary battery of il. Plante , , and the new storage battery of Profeaors Houston and Elihu Thomson. I also expressed my belief that soon by snch means we shonlu be enabled to supply charges of electricity for domestic and industrial purposes.. The following extract from the Glasgow Mail, containing remarks by Professor Sir W. Thompson on the new improvement made on the Plants battery byM.Faure.will doubtless be perused with interest by many of yonr •: readers:— ■ ; Sir Wm. Thompson, of Glasgow University, has given some-further 'details of his remarkable experiments on the storage of electricity. He writes:—" The marvellous ' box of. electricity,' referred to in the Weekly Mail of last Saturday, has been subjected to a variety of trials and measurements in my laboratory for now three weeks, and I think it may interest your readers to learn that the results show your correspondent to have been by no means too enthusiastic as to its great practical value. lam continuing my experiments to learn the behaviour of the Faure battery in varied circumstances, and to do what I can towards finding the best way of arranging it for the different kinds of service to which it is to be applied. At the request of, the Conseil d'Administration of the SocitStg de la Force et la Lumiere, I have gladly undertaken this work, because the subject is one in which I feel intensely interested, seeing in it a realization of the most ardently and unceasingly felt scientific aspirations of . my . life—an nepiration which I scarcely dared to expect or to hope to live to see realised. The problem of converting energy into a preservable and storable form, and of laying it up in a store 'conveniently for allowing it to be used at any time when wanted, is one of the most interesting and important in the whole range of science. It is solved on a small scale in

■winding up a watch, in drawing a bow, in compressing air into the receiver of an airgun or of a Whitehead torpedo, in winding up the weights of a clock or other machine driven by weights, and.in pumping up water to a height by a windmill (or otherwise, as in Sir William Armstrong's hydraulic accumu- ■ lator) for the purpose of using it afterwards to do work by a waterwheel or water pressure on a piston. Itis solved on a large scale by the application of burning fuel to smelt zinc, to be afterwards used to give electric light or drive an electro-magnetic engine by becoming, as it were, nnsmelted into a voltaic battery. Ever since Joule, 40 years ago, founded the thermodynamic theory of the voltaic battery and the electro-magnetic engine the idea of applying the engine to work the battery backwards and thus restore the chemical energy to the materials.so that they-may again act voltaically, and again and again, has been familiar in science. But with all ordinary forms of voltaic battery the realisation of the idea to any purpose seemed hopelessly distant. By Plante's admirable discovery of the lead and peroxide of lead voltaic battery, alluded to by your correspondent, an. important advance towards the desired object was made 20 years ago ; and now by M. Faure's improvement practical fruition is attained. The 'million of foot pounds' kept in the box during its 72 hours' journey from Paris to Glasgow was no exaggeration. One of the four cells, after being discharged, was recharged again by my own laboratory battery, and then left to itself absolutely undisturbed for ten days. After that it yielded to me 260,000 foot pounds (or a little more than a quarter of a million). This not only confirms 11. Reynier's measurements, -en the faith of which yonr correspondent's statement was made; it seems further to show that the waste of the stored energy by time is not great, and that for days and weeks,; at all events, it may not be of practical moment. This, however, is a question which can only be answered by careful observations and measurements carried on for a much longer time than I have hitherto had for investigating the Faure battery. I have already ascertained enough regarding its qualities to make it quite certain that it solves the problem of storing electric energy in a manner and on a scale useful for many important : practical applications. It has already had in this country one interesting application, of the smallest in respect to dynamical energy used, but not of the smallest in respect to beneficence, of all that may be expected of it. A few days ago my colleague, Professor George Buchanan, carried away from my laboratory one of the lead cells (weighing . about 181b.) in his carriage, and By it ignited the thick platinum wire of a galvanic tcraseur . and bloodlessly removed a najvoid tumour from the tongue of a young boy in about a minute of time. The operation would have occupied over ten minutes if performed by the ordinary chain icraseur, as it must have been had the ITaure cell not been available,

because in the circumstances the surgical electrician, with his paraphernalia of voltaic battery to be set up beforehand, would not have been practically admissible. The largest useful application waiting just now for the Faure battery.—and it is to be hoped that the very minimun of time will be allowed to pass till the ba,ttery is supplied for this application—is to do for this electric light, what a water cistern in a house does for an inconstant water supply. A little battery of seven of the boxes described by your correspondent suffices to give the incandescence in Swan or Edison lights to the extent of lOO.eandlesfor six hours, without any perceptible diminution of brilliancy. Thus, instead of needing a gas engine or steam engine to be kept at work as long as the light is wanted, with the liability ' of the light failing at any moment through the slipping of a belt—ah accident of too frequent occurrence—or any other breakdown or stoppage of the machinery, and instead of the wasteful inactivity during the hours of day or night when the light is not required, the engine may be kept going, all day and stopped at night, or it may be kept going day. and night, which will undoubtedly be the most economical plan when the electric Hgbt comes into general enough use. The Faure accumulator, always Kept charged from the. engine by the house supply wire, with a proper automatic stop to check the supply ■when the accumulator is full, will be always ready at any hour of the day or night to give —whatever.-light is, required. _ Precisely the e fine advantages in respect of force will be by the accumulator when the; electric r' town supply , is, as it surely will be, ; before many pass, regularly used for \tarning latbes and other machinery in workshops ind sewing machines inprivate houses. £jiothefcsvery_ important application o£ ; the • accl itaulato r is for the electric lighting of • igjjnships-N A dynamo-electric machine of verV moderate -magnitude and expense, ■, -ipTi tv a belt from tii» drum on the main . ? d pl lwan'or for mast-h 6 ad 4 4 and csOanSi 01 lamps, mtfc more : ai jed and green b ave yet been cei anty.an4Tegu- a j or any house on 1 ? 1