SCIENCE 



FRIDAY, JANUARY 25, li 



THE STORAGE OF ELECTRICITY. 



One of the greatest drawbacks to the introduction of electricity 

 as a servant of man has heretofore been a method of providing a 

 suitable means of accumulating it, so as to have it at hand when 

 and where wanted. The development of storage-batteries is doing 

 as much to-day to advance the universal adoption of electricity as 

 the dynamo when invented did to introduce it. 



To Gaston Plante. more than to any other investigator, are we 

 indebted for our knowledge of storage-batteries. He it was who 



above, the plates of metallic lead become gradually converted into 

 spongy lead on the negative pole, and peroxide of lead on the posi- 

 tive pole, and that such a cell would hold current and deliver it 

 again with but small loss. The chief reason that a storage-battery 

 of this character could not be made of use practically, was the fact 

 that to form the lead plates it was necessary to pass the charging 

 current daily back and forth by a series of reversals for many 

 months before they became converted to their new forms. 



On the discovery and perfecting of the mechanical production of 

 electricity by means of the dynamo, the production of a suitable 

 form of storage immediately became one of the leading questions 

 of the day ; but how this formation of Plant6's plates might be has- 



IBIT AT THE AMERICAN INSTITUTE FAIR. 



first took advantage of secondary currents in voltaic batteries. He 

 examined the entire problem of the polarization of electrodes, using 

 all kinds of metals as electrodes or plates, and many different liq- 

 uids as electrolytes ; but he found that the greatest efficiency was 

 produced by electrodes of lead in diluted sulphuric acid. 



The first set of Plante cells was exhibited in i860, before the 

 Paris Academy of Sciences. It was immediately recognized that 

 the storage-battery had a field peculiarly its own, and that its ap- 

 plication was only limited by the application of electricity. This 

 was all before the introduction of the dynamo ; and at that time 

 little real commercial value was attached to the discovery, as the ac- 

 cumulators had to be charged by means of primary batteries, and it 

 was then well known that electricity, when produced by chemical 

 means, was far too expensive for any purpose outside of the labor- 

 atory. 



Mr. Plante's discovery consisted of the fact, that, if a current of 

 electricity be passed back and forth through a pile composed as 



tened, so as to reduce the cost of manufacture within practical lim- 

 its, was what was first to be solved. The first step forward was 

 the artificial application of the oxides found on Plante's plates to 

 sheets of lead which were bound on by strips of felt. After a short 

 time, however, under the action of the sulphuric acid, these strips 

 of felt became eaten, and the surface of the plates fell away. 



It remained for Mr. Edmond Julien, a Belgian engineer, to make 

 a battery of such a form as to be electrically and mechanically 

 suited to the requirements. His battery consists of perforated 

 plates or grids, into which are pressed the active materials or ox- 

 ides, which, after a short charge, become almost one homogeneous 

 mass, being what Plante in a crude way produced by the continu- 

 ous action of a series of reversals of a current. This, however im- 

 portant, did not turn out to be his most valuable invention. When 

 put to practical use, it was found that after a short time the posi- 

 tive plates showed signs of corrosion, which limited their life to 

 about one year. He therefore entered upon the work of construct- 



