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7/27/2019 1891.07.18 - Literary Digest - Science and Philosophy What is Electricity?
http://slidepdf.com/reader/full/18910718-literary-digest-science-and-philosophy-what-is-electricity 1/2
Vol, III. No. 12.] TH E L I T E RARY D IGEST . July 18, 1891 (319) 11
Dintre toate formele de energie care sunt omniprzente in natura,
care sunt mereu in schimbare, mereu in i ~ c a r e ca un suflet care
anima universul inert, cele ale electricitatii magnetismului sunt
probabil cele mai fascinante. Efectele gravitatiei, ale cadurii
luminii pe care le observam zilnic, cu care ne b i ~ n u i m curand,
pierd pentru noi caracterul extraordinar minunat; dar electricitatea
magnetismul, cu relatia lor unica, cu caracterullor aparent dublu,unic intre fortele din natura, cu fenomenele lor de atractie,
respingere rotatie, stimuleaza excita mintea catre gandire
cercetare. Acum suntem siguri ca fenomenele electrice magnetice
sunt atribuite eterului; suntem probabil , justi:ficati sa spunem ca
efectele electricitatii statice sunt efectele eterului sub presiune,
toate cele ale electricitatii dinamice ale electro-magnetismului
sunt efecte ale eterului in m i ~ c a r e Dar intrebarea, ce sunt
electricitatea magnetismul, inca ramane rara raspuns. In primul
rand, ne intrebam in mod natural, exista ceva ca electricitatea? In
interpretarea fenomenului electric, ar trebui sa vorbim deelectricitate, sau de o conditie electrica, o stare, sau un efect. Daca
vorbim de efecte electrice, trebuie sa distingem doua efecte opuse ca
caracter, neutralizandu-se unul pe celalalt. Intr-un mediu cu
proprietatile eterului, nu putem exercita o presiune sau sa producem
o deplasare sau m i ~ c a r e de orice tip, lara a cauza in mediul
inconjurator un echivalent un efect opus. Dar, daca vorbim de
electricitate, intelegand un lucru, trebuie cred, sa abandonam idea a
doua electricitati. Pentru ca, cum ne putem noi imagina ca ar trebui
sa existe doua lucruri, echivalente in marime, asemanatoare in
proprietati, dar de caractere opuse, ambele agatate de materie,ambele atragandu-se neutralizandu-se complet unul pe celalalt?
Daca exista un asemenea lucru ca electricitatea, poate exista doar un
singur asemenea lucru, posibil excesul necesitatea acelui singur
lucru, d e ~ i mult mai probabil starea lui determina caracterul pozitiv
negativ. T o t u ~ in ciuda acestui aspect, teoria celor doua
electricitati es te in general acceptata, deoarece explica aparent
fenomenul electric intr-o maniera mult mai satis:Iacatoare. Dar o
teorie care explica mai bine faptele nu este neaparat adevarata.
Care, din toate lucrurile, de existenta carora noi ~ t i m , avem eel
mai bun motiv sa-l numim electricitate? ~ t i m ca ea actioneaza ca unfluid incomprehensibil; astfel incat trebuie sa existe o cantitate
constanta din ea in natura; astfel incat ea nu poate :fi nici produsa,
nici distrusa; astfel fenomenele electrice eterice sunt identice.
Bruse, aceasta idee sugereaza ea prin urmare, ca electricitatea
ar trebui sa fie eter. Trebuie sa marturisesc ca eu nu cred in doua
electricitati, mult mai putin intr-un eter dublu alcatuit. Electricitatea
nu poate :fi numita eter, in sensullarg al termenului;
SCIENCE AND PHILOSOPHY.
WHAT IS ELECT R ICITY?
NIKOLA TES LA.
Electrical Revie·w, 1\'e·w York, July 11 .
Oall th e forms of nature's all -pervad ing energy, which,
ever c h a n g i n ~ and ever moving, like a soul animates
th e inert universe, those of electricity an d magnetism are per
haps th e most fascinating. The effects of gravitation, of heat,
and light we observe daily, soon we get accustomed to
them, and soon they lose for us the character of th e marvelou s
and wonderful ; but electricity and magnetism, with their singular relationship, with their seemingly dual character , unique
among th e forces in nature, with their ph e nomena of attra·c
tions, repulsions, an d rotations, stim ulat e an d excite th e mind
to thought and research. \Ve are now confident that electric
and magnetic phenomena ar e attributable to ether; an d we
are, perhaps, justified in saying that the effects of static elec
tricity ar e effects of ether under strain, an d those of dynamic
electricity and electro-magnettsm effects of ether in motion.
Bu t this still leaves th e qu estion, as to what electricity arid
magnetism are, unanswered. First, we naturally inquire, isthere such a thing as electricity? In in terpre ting electric
phenomena, we may speak of electricity or of an electric con
dition, state, or effect. I f we speak of electric effects, we must
distinguish tw o effects opposite in character, and neutralizing
each other. In a medium of th e properties of ether we cannot
exert a strain or produce a displacement or motion of any kind
without causing in th e surrounding medium an equivalent an d
opposite effect . But if we speak of electricity, meaning athing, we must, I think, aban don th e idea of tw o electncities.
Fo r how can we imagine t 11at there should be two things,equivalent in amount, alike in th e ir properties, but of oppostte
character, bo th clinging to matter, both attracting an d com
pletely neutralizing each other? I f there is such a thing as
electricity, there ca n be o nly on e such thing, an d excess an d
want of that o ne thing, possibly, though more probably it s
condition, determines th e positive an d negative character.
Still, in spite of this, th e theory of th e two e lect ricities is gen
erally accepted, as it apparently explains electric phenomena
in a more satisfactory manner. Bu t a theory which explains
better th e facts is not necessarily true.What, of al l things, th e existen ce of which we know, have
we th e best reaso n t o call electricity? \Ve know that it acts
like an incompressible fluid; that there must be a constant
quantity of it in nature; that it ca n be neither produced no r
destroyed; an d that cit'ctric an d ether ph enomena ar e identical.
The idea a t once s u ~ g c : s t s itself, therefore , that electricity
might be ether. I mu st confess that I cannot believe in tw o
electric ities, mu c h le ss in a douuly constituted ether. Elec
tricity cannot be called ether in the broad sense of th e term i
7/27/2019 1891.07.18 - Literary Digest - Science and Philosophy What is Electricity?
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Tradus de SaDAng
12 ( : 3 ~ 0 ) TH E LTTERARY DIGEST , L uly 18. 1891.
but nothing would seem to stand in th e way of calling elec
tricity et he r associated with matter-b ound ether : o r, in other
words, that th e so · callcd sta ti c charge o f th e molecule is ether
.associa ted in so me way with the mo lecule. Loo king a t it in
that l ight , we would be justifi ed in sa ying that electri ci ty is
·conce rn ed in a ll molec ular ac ti o n. Now, prec isely what the
ether sur roun d ing th e molecules is, wherein it differs from
ether in ge neral, can only be co njectu rer\. It ca nn o t differ in
-dens ity, ethe r be in g in co mpress ible; it mu st, therefore, be
under so me s train or in motio n, and the latter is th e mo re
probable. To un ders tand its fun c tio ns it would be neces
sary to have an exact idea o f the physical co nstruction of
matter.Bu t of a ll the views o f nature th e o ne which assumes one
m at ter an d o ne force, and a pe rfec t u nifo rmity throug hout, is
the mos t sc ientific a nd th e mos t likely t o be true . An infini
t es imal world, with th e molec ules and their atoms spinning
an d mov in g in o rb its in mu ch th e sa me man ncr as ce les tial
bodies, ca rrying wit h th em e th e r, whi ch is probably spinning
with th e m- in o th er wo rds, ca rry ing w1th th em s tatic charges
- seems to my mind th e mos t pro bable vie w ; o ne which in a
plaus1
ble man nc racco
un ts for mos
t o f th eph
e nomena obse
rved.The spinning o f t he molecules and th e tr ether sets up e th er
1.ensio ns o r elec tros ta tic s trains ; th e equaliza ti o n o f ether
t ensio ns ge ts up e ther mo tio ns or elec tr ic currents, an d
th e o rbital mo ,·eme nt s produce th e eficc ts of electro and
permanent magneti sm. Abo ut fiftee n yea rs ag o Pro fe ssor
R o wland demonstrated a mos t interes ting and important
fac t, namely. that a st a tic cha rge carried around produces
th e e ffects o f a n elec tr ic cur re nt. \Ve can co nceive lines
or tu bes o f force whi ch physica lly exist, be in g fo rm ed of
rows o f di rect ed mov ing molecules; we ca n see th a t th ese linesmust be closed ; th a t th ey mus t t e nd to sho rt en and expand,
-etc. It likewi se ex pla ins in a reasona ble way the mos t puzzling
J>heno men on of a ll, perm anent mag ne tism, and. in gene ra l, ha s
all th e beauties of th e Am pe re th eo ry without possessin g the
vi ta l d efect o f th e sa me, namely, the ass umptio n o f mo lecular
c urrents. \Vithou t en la rgi ng furthe r upo n th e subjec t I would
say that l look up on all elec trostatic curre nt and magnetic
J>leno mena as be ing d ue to elec trostati c molecular fo rces.
\Ve arc whirling th rough th e e ndless s pace with inco nccivalJic speed; a ll a ro un d us everything is !'pinning, e verything is
mov ing, everywh ere is r ~ y . There n n 1 ~ t be some way of
.avai ling ourse lves of th is ene rgy mo re directly. Then, with th e
light obt a ined from th e mediu m, with th e power d erived fro m
i t, with eve ry Co rm of e ne rgy ob ta ined without cfiort, from th e
store forever inexhaus ti ble, hu mani ty will ad van ce with giant
strides. The mere co nt e mpl ati on o f th ese magnificen t possi-1
bil iti es expands our mincts, sl l e ngt he ns ou r hopes, and fills our
hearts with supt eme de light .
dar nimic nu pare a stain calea numirii electricitafii, eter asociat
cu materie - eter legat; sau, cu alte cuvinte, ca nmita sarcina
statica a moleculei, este eter asociat intr-un anume fel cu
molecula. Uitandu-ne la ea in aceasta lumina, vom fi. justifi.cati sa
afirmam ca electricitatea este imphcata in toate actiunile
moleculare. Acum, cetip de eter este cu certitudine eel ce
inconjoara molecula, prince difera de eter in general, poate doar
fi. doar de conjunctura. Nu poate diferi in densitate, eterul fiind
incomprehensibil; el trebuie, prin urmare, sa fie sub un fel de
presiune sau in i ~ c a r e , iar ultima este cea mai probabila. Pentru
a-i intelege functiunile, va necesita existents unei idei clare a
constructiei fizice a materiei.
Dar dintre toate punctele de vedere despre natura, cea careasuma o materie o foqa, o uniformitate perfect! peste tot,
este cea mai ~ t i i n t i f i c a pare a fi cea mai adevarata. 0 lume
infinitezimala. cu moleculele atomii ei rotindu-se
m i ~ c a n d u - s e in orbite intr-o manieri. foarte asemanatoare cu a
corpurilor c e r e ~ t i , transportand cu ele eter, care se r o t e ~ t eprobabil cu ele - cu alte cuvinte, carand cu ele electricitate statica
- apare mintii mele ca fiind cea mai probabila explicatie; una care
intr-o maniera plauzibila, conteaza pentru cele mai multe
fenomene observate. Rotirea moleculelor a eterului acestora,creaza tesiuni eterice sau tensiuni electrostatice; egalizarea
tensiunilor eterice initiaza m i ~ c a r i eterice sau curenti electrici,
iar m i ~ c a r i l e orbitale produc efectele electrice ale
magnetismului permanent. Cu aproximativ cincisprezece ani in
urma, profesorul Rowland a demonstrat eel mai interesant
important fapt, anume, ca o sarcina statica afiata in deplasare
produce efectele unui curent electric. Putem concepe linii sau
tuburi de foqa care exista fizic, fiind formate din randuri de
molecule in m i ~ c a r e ordonata; putem intelege ca aceste linii
trebuie sa fie inchise; ca ele trebuie sa tinda sa se scurteze sase extinda, etc. Ele explica de asemenea intr-un mod rezonabil,
eel mai enigmatic fenomen dm toate, magnetismul permanent,
in general, are toata frumusetea teonei lui Amper, f"ara a poseda
defectul vital al acesteia, annme, ipoteza curenfilor moleculari.
Fara a extinde pe mai departe discutia despre acest subiect, al
spune ca ma uit la toate fenomenele electrostatice, electrice
magnetice, ca fiind datorate foqelor moleculare electrostatice.
Noi ne invartim prin spatiul infinit cu viteza de neimaginat;
totul in jurul nostru ser o t e ~ t e ,
totul sem i ~ c a ,
peste tot esteenergie. Trebuie sa existe o cale prin care sa beneficiem mult mai
direct, noi n ~ i n e de aceasta energie. Apoi, cu lumina obtinuta din
mediu, cu puterea derivata din ea, cu fiecare forma de energie
o b ~ i n u t a f"ara efort, de Ia magazinul mereu inepuizabil,
umanitatea va avansa cu p a ~ i u r i a ~ i . Simpla contemplare a
acestor magnifi.ce posibilitati e p a ~ e ~ t e mintile noastre, ne
i n t a r e ~ t e sperantele ne umple inimile cu o suprema incantare.