The San Francisco call., 1906-12-23

was going well with him, for he had
just completed storage battery that
VIII revolutionize street traff1c and
emancipate the much-abused horse.
COMPLAINS OF PATENT Laws
Edison complains that the United
States patent laws are full of discour-
agement to the average inventor.
They do not afford him sufficient pro-
lection against pirates" If I invent
monkey-wrench,'' he said, the
chances are that 1 will get away with
it; but if I invent anything that at
tracts notice hundred pirates Will
spring up in all parts of the world to
claim it as their very own. The United
States courts are overburdened with
patent cases. The life Of a patent is
seventeen years, but owing to the laws
delay it sometimes takes that long to
get final decision. Meanwhile your
rival has been reaping the advantage
of his piracy without let or hindrance.
We should have a United States Court
of Patents"
But Notwithstanding the laws de-
lay Edison is one of the few inventors
who have grown wealthy. He became a
telegrapher and in 1870 and at the age
of % invented duplex telegraphy. Pro-
fessor Bells telephone was mere toy
exhibited at the Centennial Exposition
in 1876. The delicate vibrations OF a
magnetized diaphragm closely adjacent
to permanent magnet wound with
fine wire did not set up in the coll OF
wire energy in electric impulses sur
ficient to operate the telephone at any
considerable distance Berliner got out
patent for a contact or battery trans
mitter in 1880, but metal contacts would
not transmit speech articulately
Edison taught them the use of car
bon contacts in a transmitter. Pro-
fessor Hughes then showed that the
carbon contacts should be loose. Hun
ley brought finely divided carbon into
use, and together with Edison's induc-
tion coil to keep the primary circuit
at low resistance we have the sue
cessful telephone of today
WHAT HE HAS DONE
Edison's knowledge of the sensitive
properties of carbon in causing va
riations of resistance in the electric
current made the telephone success.
Swan perfected an electric glow
lamp" The filament was of platinum,
but Edison showed that a carbon fla
ment, if inclosed in q vacuum bulb
would remain incandescent for many
hours without perishing. He knew,
too, that carbon heated offered less re-
sistance to the electric current than
carbon cold and this has been an eco
nomical factor in its employment in
incandescent lamps He then devised
a method of distributing low voltage
current, by means of parallel circuits,
like gas.
Edison saw in the Smithsonian Insti-
tuition in Washington machine that
recorded in lampblack tracing the va
riations of the human voice in pitch
and amplitude. Each voice left its own
individual and distinctive tracings. He
wondered why, if these tracings were
impressed on tin foil or wax, they could
not be made to give back the same
sounds that had been recorded. He
experimental, and the phonograph was
the result.
Away back some time or other some
body produced a series of pictures In
book form. There were hundreds of
them in one volume. and each was just
trifie different from its predecessor
in regular sequence, so that by let
ting the leaves fly back from between
the thumb and forefinger the pictures
were blended and seemed to be NOV
ing, as if the subject were in aclion.
Everybody had forgotten this realistic
device. Everybody apparently but Ed
ison, and he recalled it when the kodak
brought film photography into practice.
PROFITS ENORMOUS.
He saw that a series of instantan-
eous photographs, each differing from
its predecessor somewhat, would, If
printed@on a long sensitive strip or
tape, and reeled off at speed greater
than forty pictures second, be made
to appear to the eye as one picture
blended so as to appear to be in mo-
tion. So he invented the kinetescope
or blograph. A Washington man
claimed priority of invention, and the
honors were divided The court de-
cided that Edison was at least entitled
to the credit for inventing the method
of reproduction.