The Norfolk Virginian. [volume] (Norfolk, Va.) 186?-189?, 1896-03-24

the cathode rays are sent out IN streams
from a bare copper wire through which
| IS passing u current OF enormously high
potential. say two or three hundred
| thousand volts. Think what that
means! During every second the cur
rent Is projected first one way and then
the other say Il quarter of n million
times. beating upon the surrounding air
two hundred and hfty thousand times In
he drawing of a breath. That il is
really this back and forward movement
of the alternating cu:rsnt that causes
such beating upon the air and hence the
cathode RAYS, Is shown by the fact tina
no such rays are produced by Il con.in-
uous current. that Is one which flows
round ana round the circuit always in
the same direction.
Each blow Of TIL So amazing little trip
hammers that work necessarily against
the air wherever an alternating current
is sent causese the layer of air about the
wire to dash i;seif agains; this surround
ing layer and so they go. these sound
waves of electrified air. back and forth.
II hundred thousand. two hundred thous-
aud times in Il second. rppling into
space. While they are invisible to the
eye. and inaudblc 10 thu ear. their i'm
pact may be LETT upon the body If one
stands near where q current of such
high potential is passing. In somc of
his experiments Mr.. Tesla has fcl; these
waves like slaps in the fac at Il distance
of several fee; from tbs wire, and 1t is
only question OF giving great enough
intensity to such current 10 produce
.fiadow pho,oGra l;hs without the inter
vcntlon Of n Croulics tube or any other
form of lamp. The lighting does this I'm
nature. for more than once il has hap
pencd in a STERN that the electric fla sil
has had photograph effect upon sur
rounding objects. and il is altogether
likely that this power Of lighting TO
make photographs Is due 10 the violent
projection OF cathode rays through the
surrounding air.
NO CATHODE RAYS IN \ VACUUM.
What the Crook=s tube does in expert
ments i'll shadow photography. as they
have been thus far conducted. Is TO facil-
ttate velocity In the little t:ip-hammcrs
The difficulty in sending forth cathode
rays from an uncovered wire lies In the
fact that the surrounding mir strata
press so closely upon the particles of air
that receive the first impact as 10 pre-
vent them from moving freely and Civ
ing strong impulse 10 the surrounding
particles. For comparison. take bot
tie filled with shot. but il YOU pour out
tire quarters OF the shot, and then
shake Ii with equal force. the shot re-
manning inside will fly about In all di-
rections and make a great commo.ion
The Crookes tube does exactly that for
she pat'icleS Vi ali. preventing them
from crowding upon the wire by pour
ing out most OF them that Is, by Great
ing what is called vacuum. but what
Is really only glass tube filled with
rarefed air. The wire of the circuit
being introduced into this thin mir buff
TETS It's particles about under the blows
OF Its swift alterations with far great
o. effectiveness than would he possible
were ii left to strike against the hcav ier
layers OF ordinary air. The difference
Is as great In the case OF n prizc-fighter
trying to Strike n blow under water or
again In the air
IL may be demonstrate ted however
that the efficiency OF the Crookcs tube
in producing the cathode RAYS is due 10
the vibrations Of the particles of rarEfie1
air within. and that withou, such rare
lied air particles. there could he no pro-
duction of the rays. Mr.. Tesla has
shown this In an ingenious apparatus de-
Nised by himself by turning an alter
mating current into a. Crookes tube in
which has been produced an absolutely
perieci vacuum. something II gardcd as
ina;tainable by most scientists bu;
possible to him. From such a Crookes
tube no cathode rays. whatever. are
found 10 emerge. for thu simple r,ason
mat the alternating shocks from the
wire having no medium TO ac: upon,
produce no effect upon the surroundinl
glass tube and hence none upon the
outside air
suggested 20 Mr.. Tesla that IL might
ne possible TO demonstrate his theory
mat the cathode nays are really sound
| waves OF electrified air. by introducing
perfect vacuum lube in the ordinary
apparatus Tor photegraphing shadow
pictures and causing the rays 10 pass
throuGh this vacuum before impingimE
| on IN" rhotoSraphic film. II is Kr.,.,y,l
vi course, that ether waves will traverse
Ia vacuum while Snuli waves v i'll not
ana II would seem that this new theory
! W"nlu ihus be put To the test, Since ii
me riatc was affected by the rays in
! spite OF the Nacuum> il would show that
! 'hcN WeI" not sound waves, while If the
vacuum prevented it from being scnai-
tized then Mr. Tesla's view would be
sustained.
Such an experiment. would b. inter,
rsting, he said. but it would not he
conclusive. since the cathode 1ovs
once started. move with such incredible
velocity that they would jump through
any ordinary vacuum. | estimate that
the AR particles III Il Crookes tube set
III VIBRATION by a high potential cur
rent, are hurled back and forth at the
Fa'c ni from three to five kilometres n
second. In order to overcome tiis great
momentum il would he necessary L.
produce vacuum occupying Il CunSil-
cradle space, and that is not easy 10 do
sun. | am sure shat before long th.
scientific world will recognize that thos.
cathode rays are The Identical sound
waves OF electrified air which 1 an.