The Columbian. [volume] (Bloomsburg, Pa.) 1866-1910, 1893-03-24
The Telephone Paten to.
AFTER JANUARY 80, 1904, ANYBo Dy
CAN MANUFACTURE TELEPHONES
WITH MAGNETIC TRANS y
MITTERS.


Much public interest has been ex.
cited throughout the country BY the
announcement that the patent for one
of the important features of the Bell
telephone was about to expire. A
search of the records of the patent
Office disclosed the facts that the pat.
ent granted to Alexander Graham
Bell, March 7 1876, expired on Tues.
day. This patent covers broadly the
art OF transferring to, or lmpressing
upon a continuous current Of electricity
in a close circuit, by gradually chang
ing its intensity, the vibrations of air
produced by the human voice in
articulate speech, in way to cause
the speech to be carried to and re-
ceived by listener at distance on
the line of the current" Briefly stat
ed, the situations as to the Bell patent
are these.
Letters patent to Prof. Bell, grant
ed Jan. 80, 1877 will expire January
80, 1894. The supreme court has in
this patent sustained claims tor a
sounding box, for a speaking tube or
a mouth piece, land for a metallic
diaphragm, broadly. These details
are SO fundamental that a commercial
instrument could hardly be constructed
without them.
The foreign patent to Bell covers a
receiver, and was filed December O.,
1876, and expired December Q, 1900.
1t did not become patent until May
IS, 1877, SO that the United States
patent to Bell of 1876 would not be
limited by this foreign patent, because
the invention had not been previously
patented" within the meaning of the
statute, prior to the 1876 foreign pat.
ent to Bell.
The patent to Hunnings in England
of Sept. 80, 1873, expired Sept. 80,
1892, This patent covers a
microphone, with comminuted or
powdered electrode. While it may be
true that the patents in this country
on such microphonc have expired,
yet it is not to be overlooked that a
patent has recently been issued to
Emile Berliner which covers micro
phone broadly-,hat is, a contact tele-
phone depending upon pressure be-
tween the electrodes. 1t also must
not be overlooked that patent was
issued May 3, 1892, to T. A. Edison
for microphone with high resist
ance electrode, broadly. 1t covers a
species of the genus covered by the
Berliner patent Il is to be presumed
that the Edison and Berliner patents
are valid patents until court Of COM
petent jurisdiction has declared the
same invalid. The foreign patent on
the invention covered by the Edison
patent has expired under such circum-
stances that it may fairly be said to be
doubtful whether the latter be valid
patent 1t is we'll known that a suit has
recently been brought in the United
States circuit court of the district Of
Massachusetts TO annul the Berliner
patent.
Assuming that the Edison and Ber-
liner patents are valid patents in law,
it is clear that, Notwithstanding the
fact that the invention covered by
the Hunnings patent may be public
property in this country, yet if any one
not authorized should use it, he might
be held to be an infringer Of the
Berliner patent.
The patents covering so.called
"Blake transmitter'' expire shortly.
They cover, briefly stated, pendulous
electrodes, diaphragms held In place
by a spring, and mufflers acting as
diaphragms.
1t is fair conclusion to reach
therefore, in view Of the present state
of the said patents relating to tele-
phones, &c, owned by the Bell Tele-
phone company, that there seems to.
be no good reason why, after Jan. 80,
1894. telephone having a magnetic
transmitter should not be put upon
the market without danger Of infring
ing other patents This at least is the
opinion expressed by the chief
officials Of the patent Office.
AS to central exchanges, it may
fairly be asserted that a primitive but
serviceable exchange may be used
without infringing any patents (of
which there are many), because,
possibly, anticipating telegraph switch
boards. Until a court Of compel ent
jurisdiction has passed upon the varl-
Gus questions involved, it is not safe