New-York tribune., 1896-11-29
; a metallic re

towns especially on lines not having a metallic re-
turn. II is still in favor. ,,, -
Edison had Il transmitter. utilizing varlaDle pres
sure In the contact of platinum terminal WIN a
specially prepared carbon disk as early as lo.'.
But he did not take out patens un s a'% of
Scores Of others have employed the same principe.
and have shown marked preference tot n, faos
"microphone" by Professor Hughes In lss' seemed
to demonstrate the peculiar fitness OF that nnatera'
for the purpose: and subsequent experiment con-
firms the theory.
one OF the famous transmitters was Hunnings.
He introduced carbon in minute granules between
plates disks. one or both OF when were NOV
able The original Iiunning patent; issued In issl.
g psed I'm 1892 but other men have followed up the
idea changing the arrangement. OF details IN ord~r
to higher efficiency. The 'solid-back trans
mitter now employed the long distance line be-
tween New-York and Chicago. utillzes granulated
carbon the latter being so arranged that VIII not
pack in other transmttcrs and Is one OF
the latest developments along this line OF invention
The foregoing facts VII: assist one to understand
the Berliner case In 1916 1871 Emile Berliner ap.
piled for a patent on "A piece OF apparatus Intended
both for receiver and a TRANSMITTED II workel
with induction coil. battery and the Varia Ole
pressure between two carbon terminals These
last were somewhat different in form from any OF
the other Instruments referred TO- but not 10 any re-
markahr degree. After the papers were filed the
application was divided. and separate patents were
sought on receiver and transmtter. The receiver
patent granted In 1877 and Will expire in about
two years. The device has never come into gem
eral use as a receiver. however and probably never
will The new application on the transmitter was
fled In November. 1880 and the patent was issued
November T. 1891 fourteen years after (, first
asked for The transmi,ter too inferior 10 older
apparatus designed for the purpose, and
therefore Il has proved OF no practical value. No
inventor would be tempted to initiate II. And
the owner Of the patent the Bell company proba-
bly, has no thought OF Introducing the device.
But unlike .he patents OF other similar apparatus.
the Berliner patent claims the right TO us" the
principle OF variable resistance" In any form Ii
Is exceedingly broad and sweeping In It's language.
and II the Supreme Court should pronounce II
valid. any kind OF variable resistance trans
miicr would be an infringement.
In his suit to annul the patent. Uncle Sam alleges
that the astonishing delay in the issue of the now
famous document unlawful. and. so far as the
Bell company responsible for 1t. act OF
bad faith toward the public. II * further pointed
out that the particular form OF apparatus described
is Identical with one covered by the patent OF 1877.
Irregularities OF procedure. especially in the intro
duction OF matter into the application ar" al
legged Finally II Is maintained by the Government
that the principle OF variable resistance was sue
cessrully employed In OF Bells experiments in
1876 and Is not new with Rcrlper. In this connec-
tion the following passage from "A Manual OF
Telephony" by Preece and Stubbs standard au-
thority. IL interesting reading The language quoted
is Lord Kelvins
1T is true that the physical principle applied by
Edison his arbon telephone ns1I) and by Hughes
in his mcrophone Is the same. but Il Is also the
same rs that employed by cerac. Of the French
Telegraph ONCE. In his variable resistance tube.
which he had lent TO Mr.. Hughes and others In
1876 for some important practical applica tions.
This apparatus Is. however. entirely dependent
upon n fact enounced long ago by Du Moncel-that
the Of pressure between two conductors In
contact produces a diminution In their electrical re-
sstance'' Messrs. Preece and Stubbs blythe way.
concede that EGsons discovery that the resistance
of carbon varies under changes OF pressure. while
later than Du Moncels. nevertheless indo-
pendent and original