The Mason County journal. [volume] (Shelton, W.T.) 1886-1927, 1890-01-31
CANCERS or ELECTRICITY.
Inventor Edison Talks of High and Low
Tension.

Inventor Edison Talks of High and Low
Tension.
The first electric light station erected
in New York had only 100 volts pres
sure, and there are 10000 lights on a
single pair of conductors. Speaking Of
the transformers or pressure reducers
used to break the current for use in res
licences and buildings, Mr.. Edison
characterizes them as dangerous for
they are liable to get out of repair, and
then the full high tension current was
apt to put it's full force inside, and any
one touching the wire with ones feet
on damp floor would be killed. The
light-pressure wire might come in con-
tact with the telephone wire, and
touching the metallic parts of the tele-
phone when standing on moist floor,
or in contact with anything which is a
conductor in connection with the gas or
water pipes, would produce the same re-
suit.
He was in favor of restricting by law
the voltage on electric-light wires in a
and control of boilers. The pressure
could be inspected by a self-recording
pressure gauge and restricted to certain
limits. If the pressure was placed by
law below the death point, it would be
totally unnecessary for the inspectors
to inspect wires or insulation, or make
any test as it would be matter of in
difference to the public what kind or
how bad the insulation may be.
L. l.. e ~ 1<>I
as follows: The low pressure of 22O
volts, which can be just felt; the
high-pressure continuous current. used
with some arc lights of 1900 volts or
more, and dangerous; the high-pressure
semi-continuOus current, used in arc
lights of 1900 volts and over, which is
exceedingly dangerous, and the alter
mating high-pressure current from 1000
volts and over between the extremes OF
the waves, which produces death in
simultaneously.
Mr.. Edison said that there should be
safe limit of about 600 volts if the cur
rent was continuous. Such a current
could not kill, though it might injure.
Of insulation Mr.. Edison said there was
none absolutely perfect, and the action
of air and water would make it brittle,
and often touch would cause it to fall
off the wire. With tremendous cur
rent of 1900 volts flowing through the
wire, or where an alternating current
was used, power of 1000 volts, it was
plain lineman took his life in his
hands when repairing such wires. He
might have some chance for his life
with overhead wires, but none in the
manhOle of a conduit.
A descriptive discharge may occur in
any such spot, and then practically
every wire in the subway is crossed, be-
sides burning out the conduit Upon
one occasion, coming under Mr.. Edison's
observation, a descriptive discharge fused
every thing round it, including cubic
yard of granite paving stone, into one
mass. A leak through the insulation
of one of the high-tension wires would
soon cause general fusing of all wires,
and the danger to those in houses would
arise in the manner pointed out. There
was no municipal ordinance in New
York, as in Chicago, regulating the
maximum leakage from dynamos. The
fear of descriptive discharge is the rea-
son why the ocean cables are operated
ut such a tension, which is barely more
than forty volts.
In conclusion, Mr. Edison pointed out
the reason for so many accidents. He
said man might hang free in the air
from wire carrying current of 1900
volts without injury, but if the feet
touched the ground and the current was
making earth at some other point of the
circuit death would result. So in a
house broken insulation might connect
the current of high-tension wire with
- gas pipe or fixture, and any contact of
the person with a damp floor or sub
stance to complete the circuit would
cause death if the metal was touched
n. Y. Letter.