Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1898-11-13
SPARKS TELEGRAPH.
ANOTHER METHOD Of WIRELESS
COMMUNICATION DISCOVERED.
ULTRA VIOLET RAYS TRANSMIT
Re.uIt, nm Electric Dischnrge-'"'s
piscbarEe il Utilized to Record
x...,r. That Cannot Be Read by
Any But Sender and Receiver.
,corr,,rondence of the DIspatch)

fCorrospondence of the Dispatch)
LONDON, November 4-W'reless teie-
eraphy I'm novel form is the newest
idea I'm nessage-hashing. Rays OF hght
are the means employed. The idea IS
based on the discovery made by professor
III. Hertz that light rays of smaller wave
length. particularly ultraviolet rays ara
able TO start an electrical discharge
working on this idea with view to III
venting a system Of biography that
would make communication possible DE-
tween two points without the ala Oh
wires q prominent electrical scientist Oh
this city began experimenting, ana soon
found that by drawing out the spneficai
electrodes of an induction coil unul
shark no longer appeared between them'
and then throwing the rays Of ultra
violet light on the space where the spark
appears, discharge Of sparks immedl-
ately resulted. The cause of this, as Oh
many more light effects that have peeh
produced of recent years, has yet TO De
discovered. The practical use TO Which
the discoVerer proposes to apply inns
means OF starting a spark discharge Is
TO telegraph TO lighthouses, ships. or I'M
der any circumstances where wireless
teleeraphy is needed or where the wire
system cannot be used.
After starting the discharge of sparks
by means of the ultraviolet lays. d.
rected on the electrodes. receiver Is
set TO catch the stream of sparks In the
experiments there were used first Dell,
then a telephone, and finally a Morse
ink-writer.
The apparatus employed was an arc
lamp placed in such a position that IL
could be used as a protector. when IL
was necessary to throw the light a great
distance mirrors were used. not OF glass;
but of quartz, so as 10 permit the ultra
violet rays to pass through them. Inc
usual telegraph signals of dot and dash
were produced by opening shutter IN
front Of the light rays for longer OF
shorter time as required.
The most interesting part of the ex-
periments is the way in which the dis
charge of sparks made by the ultra-Vio-
let rays being thrown on the spark-gap
causes the bell TO ring or the Morse INK
writer to do it's work. AS soon as the
shutter in the transmitting station IS
opened the ultraviolet rays from the
arc lamn fall on the disc electrode and
SHARKS pass across the gap, ceasing as
soon as the glass shutter falls and shuts
off the active rays. The sparks produce
feeble electric waves, which actuate d
coherer fitted with a Taper and placed IN
proximity to the apparatus, by means Oh
which the signals are received on an
electric bell or Morse apparatus
Experiments have shown that these sig
nails can also be received by using
place of a coherer, a relay connecte
i'm the secondary circuit in series with tr
IL ~
means of constructing this final re
ceiving mechanism is reserved TO be de-
termined by future experiment II the
signals need only be made audible, and
are not required to be printed the SIM
pie connection of telephone IN the
spark-gap circuit sufilces. The msula-
ton of the winding Of the telephone must
be Of a nature corresponding TO Inc pres
sure in the secondary circuit of the IN
duction coil An ordinary telephone gives
signals audible at about one metre from
the instrument, and by the use of loud
speaking telephone the effect can be IN
creased so as to be clearly audible IN
any part of a very large room Nheh
the message is read by the inaudiDle
system it has the advantage over otner
systems of communications by flashes OF
light of being as secret as the ordinary
method of telegraphnS.
The gentleman who has carried on
these experiments and brought them 10
such q successful stage thus describes
his efforts TO perfect his apparatus ana
work out his idea OF wireless telegraphy:
81 began my experiments with a distance
of . metres between the source OF hght
and the spark-gap. ~ Slemens and
Halske arc lamp was used. taking 10
amperes at Al volts, and with an arc OF
LIS nm. to nm. long. The lamp was
pIaced behind circular opening PROVIDED
with a glass shutter, the rays falling on
the spark-gap through this opening. AS
electrodes. two circular brass knobs OF
u nm diameter were used, connected
to the secondary Of a en-. spark induc-
ton coil. with a mercury interruptar. \
! fixed spark-gap was used, and the adj
iustrnent made by a resistance in the
! urinary circuit as in all my experiments.
| with a distance of 4 nm. between the
| electrodes. a spark occurred as soon as
| the glass shutter was removed from In
| frost of the arc lamp. A coherer placed
| or , metres from the spark-gap respond
| ad "a the movements OF the glass shutter
| and actuated a Morse ink-writer. AS
| soon. however, as the distance was in
| creased above metres, the apparatus
| no longer worked In Il reliable manner.
| The addition of quartz lens In front
of the spark-gap. by means of which
! the rays were concentrated on the mega
| tive electrode increased the distance over
which signals could be transmitted. Win