Evening star., 1902-01-25
WIRELESS TELEGRApHY.

1 A.SS. Tx. ~ W. Saker ana n&rkteaNcs
WIRELESS TELEGRAPHY.
Discoverer. and Practical Inventor.
OF the Various Systenas.
On account OF the prominence which
wireless telegraphy has attracted by It's re-
cent achievements and its great possibili-
ties of becoming an important factor in the
commercial world. It is very interesting to
note the various stages by which this i'm
portant method of communication has been
reached and OF the many scientists to
whom the world is indebted for the present
efficiency of the system.
In 1850 Prof. Henry of Washington. ID. c.,
discovered that particles of carbon and
steel were very sensitive TO electrical dis
charges, and would act under electrical os-
citations through the air (this being the
forerunner OF the "coherer) being an inn
perfect electrical contact. Prof. Hughes OF
London, in 1880, also experimcntcd with
aerial" telegraphy with some success.
In 1882 Prof. Amos Emerson Doibear OF
Tufts College, Boston, Mass, applied for a
basic or art patent for wireless telegraphy
and telephony. After being held In the
United States patent Office for four years
the commissioner of patents demanded a
working model Of the system. claiming that
they could not understand IL, as IL was a
unknown to them. Prof. Dolbear supplied
the apparatus, making a practical demon-
stratfon of the same, and was granted a
patent October 5, 1886, ft being the nrst
patent In the world of a practical working
wireless telegraph apparatus Prof. Dol
bear worked his system In actual practice
at that time between Blue Hill and Boston
Light, distance of over thirteen miles. 1t
is claimed that all who are using wireless
telephony and telegraphy in the United
States, therefore, necessarily infringe upon
this basic patent which is still in force.
Prof. Heinrich Hertz IN 1850 explained the
phenomena of electro etheric waves and
established the fact, by demonstrGt ting
that these waves were identical witi the
ordinary light waves, having the power Of
being reflected and refracted, thus solving
the curious phenomena which had puzZls I'd
savants up to that time.
In 1887 Sir William Preece experimental
with wireless telegraphy IN the English
channel. and subsequently rendered able
assistance to Signor Marconi
In 1890 Prof. E. Branley of Paris discov-
cred the small sensitized tube called the
"coherer," the connecting link o. modern
wireless telegraphy.
In 1891 Prof Oliver Lodge of Liverpool
sealed the "Branley' tube after having eX-
hausted the air therefrom, thereby making
it more sensitive.
In April, 1895. Prof. A. s. popof. dis
tinguished Russian naval officer (professor
in the torpedo school for officers, con-
structed, demonstrated and operated the
first modern and complete wireless tele-
graph apparatus, which. with slight modi-
fications, is now used in ali systems the
world over and this system Is now in sue
cessful use by the Russian and French
navies. Prof Popoffs invention was so re-
markable that 1t was heralded far and wide
by the scientific journals of the day. which
published treatises and illustrations, the
leading electricians of the world believing
fIao had 2 haa,, I'D H.
ing made so plain that any one ordinarily
versed in the electrical science could con-
struct such apparatus from his description.
In July, 1897. Senor GugglielI1o Marconi
received United States patent for an ap-
paratus constructed on very similar lines
to that of Prof. Popof, as was printed and
Illustrated in the Russian and French scien-
tidc journals In 1895.
Prof. Marconi has attracted world wide
attention by the successful opera tion of his
system. teiegraphing across the English
channel between Dover and Calais In
March, 1899, and subsequently, erecting
wireless stations across the English and
Irish coasts. In 1880 Prof Marconf re-
ported the international yacht races, a
license for this purpose having been
granted by the owners of the DolbeaT pat
ent to the New York Herald under whose
auspices Prof Marconi was then employed
for this purpose.
Prof. Slaby of Berlin. Germany. is also
the inventor of system which is now used
In the German navy, and over which the
Emperor William is very enthusiastic.
DE-. Dietz made many experiments with
spark telegraphy' before Marconi was
ever known to the public
The various further inventions and i'm
provements in wireless telegraphy in Amer
ica have since been made by Profs. Collins
Shoemaker. Davis, Tesla, Pickard Fessen-
den and Eshret.
On April 1, 1901, Signor Marconi surreu-
y Il, -~.,s
imperative and too broad, I'm his claims
citing that Prof. Popoff having eighteen
months previously published a discovery
and system similar to his, and therefore,
after claiming his ignorance of this fact (at
the time Of filing same). he was granted a
modified reissue in June, 1901.
Quite recently Prof Harry Shoemaker a
rising young American inventor, has made
telegraphy, for which he has received four
teen American patents, as well as patents
in foreign countries. Prof Shoema ker's
patents mark an important epoch in the
art of telegraphing without wires. covering,
as they do. a complete "selective" system
by which Interference is entirely obviated
Prof. ShOemaker's tuning system Is also
very remarkable, it being. II is claimed
perfectly adapted to practical and CONNER
cial uses.
Prof. Nathan Stubblefeld of Kentucky.
who recently came upon the scene with a
wireless telephone. and who Is reported to
have successfully talked from his residence
to the court house. a distance of about
three blocks, is making progress on the
lines Of Dolbears invention.
The practical field for wireless telephony
and telegraphy presents one Of great prom
ise and possibilities in the saving of lives
as well as cheapening construction and
communications between distant points
and while It Ii not believed it, will imme-
diately displace telegraph and cable sys-
TENS, any more than electricity has dis
placed that of gas. yet IL 1t makes as much
progress In the future as it has IN the past
two years the death knell of the poles
wires and cables and expensive messages
has surely been sounded. The demand
and uses Of the wireless system Is con-
stantly increasing.