Twice-a-week plain dealer. (Cresco, Howard County, Iowa) 1895-1913, 1908-04-24
WIRELESS 'PHON|NG.
PouLsEN DECLARES VOICE WILL
CARRY ACROSS SEA.
inventor Tells OF 2so-MiIe Test
Loss OF Power BY Undamped
Waves Less Than In Spark
ling Waves Of Wireless.

Copenhagen.-The wonderful achieve
ment of Valdemar Poulsen, chronicled
In the newspapers of the world few
days ago of carrying on conversation
OF wireless telephony between Lying
by and Weisensee, was the result Of
years of experimental work. Mr.. Poul-
sen, assisted by staff of Danish en-
gineers, has been at work for long
time in undertaking to make telephon-
Ing by means of his undamped and
continuous waves practicable and use
full in commercial transactions.
When Mr.. Poulsen had about fin
tshed his work with the wireless tele-
graph he had become convinced that
the transmission Of oral human
speech through the air was possible
and at great distances, if he could con.
truct an apparatus for transmission
and recording sufficiently strong and
powerful. He began experimenting at
once at his wireless station at LYING.
by. five miles from Copenhagen, and
demonstrated that wireless telephon.
ing could be carried on over consid.
cradle distances without losing any.
thing in clearness and distinctness.
Having made this demonstration, Mr..
Poulsen undertook to improve his ap.
paratus, and almost every day In.
creased the length of the line over
which he held conversations with his
assistants.
Finally, he had come to have so
much confidence in his system that he
undertook the risk of trying to speak
over a distance of $50 English miles
that being the distance from Lyngby
to Weisensee. near Berlin. When Mr..
Poulsen, at his station at Lyngby,
clearly heard the voices of his assist.
ants and understood distinctly all that
they were saying to him from their
station at Weisensee, he was over.
joyed. There was a perfect exchange
OF conversation between the two sta.
tons.
The difference between the spark.
ling wireless waves and Mr.. Poulsen's
undamped wireless waves accounts for
the great result which Mr.. Poulsen has
achieved. Mr.. Poulsen himself defines
the difference as follows:
The wireless sparks are to be com.
pared to the shell from big gun.
When fired, you get an enormous
blow like that caused by an explosion,
but the force of this blow is lost after
short time, the undamped waves
produce a sort of singing vibration of
enormous rapidity. and they 60 on
their way around the globe with the
same force as that with which they
leave the transmitting apparatus.
Nothing can stop them, not even
the highest mountain. They cannot
go through the mountain, but they go
singing over it, and then pass along
until they reach the receiving appara.
tus to which they are appointed.
1T will be easier for the waves to
cross the Atlantic, and of course the
North sea. than to go from Weisensee
to Lyngby. The station at Lyngby is
unfortunately situated for wireless
telephone conversation, especially with
the station at Weisensee, which also
IS badly situated and equipped"
Valdemar Poulsen, who is only 80
years old, is the son of judge in the
high criminal court of Copenhagen,
He is a very modest man and has not
as yet developed any business in his
telephone work. He is singularly
silent man, but when anyone ex.
presses an interest in his work he is
willing to explain 1t to him to the best
OF his ability and with a never-failing
enthusiasm.
Proud Of His Ancestors.
8 Bill-What in the world do you sup
,,nco mn kac whales hlow So nuch 2