■\\ 



X.-l TURE 



[I'lHKUAKY <). 1899 



r«lU, itiving ii|)|iroximnlcly twenty tluwsnnd volt*. This 

 l«ttfry I'hnrur* Lcyclen jatri or Kiiinklin plates, in 

 iiuilli|ilr, rtiiil a simplr n\ri hanual lOiUtiviimc rnahlcs 

 inr to iliscli.iijjr thrin it) >riic>. Www I )\ave lollownl 

 thr )ialli imlu alril by I'lanio ; Init toy r\i>ciiiueius have 

 iinrinl a 1. 11 (jiratrr laojjr. 



I'hr >liM liaises in oitlinaiy aii |itiHiureil by my 

 ap|)aialiiN, «iil< a vollajjc nl tbicr luiUions, are fi-on\ dj 

 (eel to r ''"et in lengtli. I'lol, Kbbu 1 bonison bas ob- 

 taincil ibM bai(;es of (xi iiii brs l>y incanv ol tiansfoimeis. 

 Tbc ibxcbaixe-- piO(bi« ril In my .ippaialu-. -.hoiiUI be at 



le«»t 111 feet in lrnj;th : for the relation between spark- 

 lenjjth anil voltawe iN ilosrK lepieventnl by a strniKht 

 line between ibe liiwilM ol twentv tlinuNaml \oltv and one 

 million voltn, rills line, limvevei, beyoml one million 

 volts, iiiixes towaixls the a\is lepivseniin); the \oltaue; 

 anil this lUivatmx" is an evpirssion ol the loss whiih 

 mines Imm the lapiillv in<irasin,i; lomliiilix il\ of the 

 nil. riiis ilimimshuii; imli.il lesistanie ol onlinaiv an 

 is the most >iiikinj; lai 1 biiMi>;bt out by mv rvpeiiments, 

 Uefoir ilesi iibmj; the elVc. Is ol sii<hhi>:h elerttomotive 

 loives, lei me speak ol llie m.iin Ir.ilnirs of the stoia);e 

 iMtlery. Their air, as 1 li.ivc mcnlioncil, ton thousand 

 vrllsi, whiih consist ofoivlinaiy tcst-tul>es with corinnatnl 

 lead strips, whuh ar« sepiuatc<l fmm eaih other by 



hinh elei tromoti\e lories are generated, rciiuired a com- 

 plete depaitnie lioni the method employed by I'lanti? ; 

 and consists in the main, of a system of lexers which 

 obviate short cm uitin);. V\f,. i exhibits ihis ap|Mr.itns, 

 which, in a leil.iiii sense, can be lei inrd .1 step up con- 

 denser, riic li^;iiir of the operator shows the si/e of the 

 apparatus, which piodnces in ordinaiy an a s|>aik <;o 

 inches in lenjjlh. .\ larjjer np(t:iratns, constructed on a 

 siinilai pl.in. en.iblc- me In experiment with discharges 

 f>,\ to ~ leet m lrii^;lh. 



I w ish, especi.div, 10 call attention to ihe results obtained 

 with this latter more poweifnl apparatus, which ){i\cs an 



electrical tension ol three luillion volis. At this tension, 

 )\tmospheric air ai oixlinary pi-essure behaves like a fairly 

 f;ood condiii 101, .mil exhibits an initial lesislance of less 

 thun a ihousanil ohms between poinied terminals live or 

 six inches a)>«ii. Resistances of distilled waiei, or of 

 ordinary city walci, contained in i;lass tubes, ol lenutb 

 not cxi enlin); six or seven feel, cannot be emploved ; 

 for a sp.iik passe inside the tubes close 10 the walls — 

 pirsnm.ibly ihii>ii,i;h a layer of aii and ihe heated air 

 •battels tlir iiibcv The sjwik will p.iss lilieen or more 

 inches over the muI.ico of water, in pielcirncc to |>assin)< 

 the same dist.in. c thron);h it. Ki>;. ; is a photo^;ranh 

 of such a spaik p.issinj; over the surface of water. Tne 

 terminals of the machine weir iuMiiersed in the w-Her, 

 l»(\een inches apait The photoj;iaph show s the irtlection 



Mibbri ImuiIv I'he^e snips air immei^e^l in dilute sul- 

 phniic and ; and thu^ lon^niuie I'lante cells The test- 

 tulH<s air held upright in woovlen blockv which ha\r 

 been ImxiImI in (taiallin. lead wiirs air einplovrti to 

 conneit the i-rlls with each other and with thr switch- 

 bivuxls. The cells air chai|;ed in multiple fc^rty iflls 

 l>rini! in each branch cinniit and a system ol swilrhes 

 i« einployr\l to thixiw the cells into senrs. Ki|{. 1 shows 

 thr ly|»r of i~rlls 



The i-\wstniction of the aP|Vlialus lor charjinj; the 

 1 ewlrn i*i-s in multiple and ilischai>;ini; in senes when 



NO. I ';iS. vol.. 50] 



■ of the sjuik li\>m ibe surface of the water, and thus 

 givTs two \ lew s, NO to s|>eak, ol diiVeirnt sides of the 



I snark. No libbon etiex-t is observable, and an absence 



I of n »<»!'•■'); I^'»th IS notii-rable. 



I A ^>e^•uliar sliatnietl api^earance is seen in photO);raphs 



! of the brtish discharjje from the jy^sitne jwle. Kic. 4 

 shows this stratification. The i^le consisted of a 



I metallic sphere one foiM in vliatnetet, Kij;. 5 exhibits 



! the brvish liischaijje frx>m the nejjatne jH^le. In l->oth 

 cases these are pliotO|ti5»phs of single discharges, which 

 are thus seen to consist Iwth of forkexl white d~isch.ir)!es 



