The sun. [volume] (New York [N.Y.]) 1833-1916, 1899-05-16
WIRELESS %TELEGRAPHY.
NEW PATENT GRANTED 70 MIRC0NI
COVERING IMPROVEMENT

1t Protects the Apparatus for Receiving
the Hertzian waves from External In.
tcrference-PreviouS Patents Covering
Apparatus for Wireless Telegraphy.
WAsHfSGToN. May ia new patent was
granted last week to Gugliclmo Marconi. as
aiRnor to the Wireless Telegraph aud Signal
Company OF London. covering improve
ments in his apparatus for wireless telegraphy.
In his later apparatus Marconi has endcavored
TO provide n workable com animation OF a trans
mitter and receiver. to either of which an aerial
conductor may be attached for sending or TAX
ing messages. His original patent Of July 13.
1897. the first granted In this country on appa-
ratus for the wireless transmission OF signals
by means OF Hertzian waves. covered such
q combination. but IN practice the sparkling
appliance for the creation and ansmiss
OF the HertZian waves was found TO inter-
fero with the sensitive tube intended for
their reception. To obviate this objec-
tion Marconi. in his last patent. has in
closed the sensitive tube in a metallic box.
having only Il small Opcning. the transmitter
being exterior to this box. The aerial con-
ductur. from which the Hertzian waves are
projected into the atmosphere. consists OF q
single wire. carried upward to whatever height
deemed necessary. and is fitted at the lower
end with a plug. which may he connected at
will with either the transmitting or receiving
instrument for the sending or taking Of mes
sages. In Marconi's former apparatus a n metallic
sheet was used to dispense the Hertzian waves
instead Of the single wire. The recording in:
strument Of Marconi's new apparatus II placed
outside the box and carefully insulated there.
from, so as not to Interfere with the sensitive
tube. In n word. therefore. the main idea OF
Marconis improvements is. the protection
of the sensitive apparatus for receiving tho
HcrtHlan waves from, external interference
Transmitted 10 it by the aerial conductor.
Besides Marconi's two patents but one pat
rat,is for Pe wirs sI.@a't ,"lcgraphy by D"m means ~ Of e The
Hertzian waves. making three In all. The other
patent was taken put Aug III, NJ, lSesi by Oliver
feature Of Lodges apparatus is the use of an
induction coil in his transmitter To increase
tansify their fore" and persistence. Lodge
maintains that the receiver of his instrument
waves of certain rate pr frequency Of vibra;
ton sent out from a particular ~transmitter, and
to individual stations without disturbing the
receiving appliances At other stations which are
t tnmso s 9f ign'f the rro tb1l a " OF the secret tre9t teaHs.
mission of wireless messages. His instrument
can be used either as II receiver or t%ransimitter
Lodges apparatus Is the use OF metallic
cones c;Gaali sI cara"i,E nrshs.. for the radiation
claimed that vertical electric oscillations from
these cones are loss likely to be absorbed in
water Some electrical .exper's consider
L2rd4ge,S apparatus supcrior to Marc2ni's
me three, patents To Maroon ana Lodge are
not the only ones granted in the United
States covering cOntrivances for the wireless
transmission Of messages or signals. Inventors
have been busy since 1854. when the first Eng
lsh patent was granted. trying to utilize their
more or less limited knowledge concerning the
transmission of ,%elertric waves through atmos-
pheric media, Earlier patents ,wer" based on
the now obsolete systems. Of electromagnetic
induction. electro-static induction. or simple
conduction. one of the earliest OF the first
named systems was that of Smith. patented in
1881. for signalling. to moving trains. OF sim
liar nature was fIlSOn'S DateDt in 1SID on
an apparatus for signalling to trains. Phelps.
in 1884. and Woods. in 1887. obtained
In 1894. patented n condurtlon apparatus for
signalling ships at sea. All these patents were
granted in the United States. There are
numerous English patents covering the same
ground.
1t is worth remarking that the Patent Office
electrical experts shareCen. Greely's skepticism
"a to the value. commercial or other. of present
methods OF wireless telegraphy. The claims OF
the inventors, they say. do not tally with the
practical operation of their Instruments.