New-York tribune., 1899-12-04
| latter on its side will win the race, and notmns
| can prevent il.
Electric POWER TRANSMISSION.

| An increase of few feet in the length OF ail
| ,,ooo,, e+comship or of half n knot in her speed
over TINT of her predecessors Is regarded mat
| Tor os much importance by the general pubic,
| os well as by marine architects and engineers
| yo+ oven moro remarkable advances have been
made ir applied science within the last nan
deem Years When the transmission of power
in the form of electricity over long lines began
IN this country the highest pressures used were
between 5000 and 10000 volts. When the line
between Niagara and Buffalo was put in opera
ton. In 1896, :he current was sent at loooo vons
for time, although the pressure was oouoieu
inside of a year. The voltage employed on the
famous Folsom Sacramento line In California
was 1000. BY degrees on some OF the later
transmission lines these limits have been ex-
ceeded until, as DR.. Louis Bell points out in the
current "Cassiers" pressure of 4O,ooo VOLTS Is
now in successful use.
The pressure at which electricity is sent over
a wire is more significant from commercial
noint Of view than is the quantity transmitted.
The higher the pressure the more economical is
the enterprise. The conductivlty of given
thread of copper increases as the square of the
,ressure. Less metal Is required, therefore,
with high potential than with low one. 1t Is
purposes only, far above that at which the cur
rent is TO be used at its destination, and then at
the latter point transform it down again to the
proper level for lighting operating cars ana
other industrial uses 1t follows, then that the
limit of the voltage possible on line determines
the distance TO which power can be economi-
cally transmitted. And on this often depends
the choice of n site by manufacturers who are
intending to employ electricity.
After the great power plant at Niagara was
ready for business most of the Industries tnat
were TO make use of the facilities thus offered
were established close TO the Falls, and mag
nincent development is now taking place there
on that basis. Nevertheless there has been
much talk about the possibility of transmitting
power from the cataract to cities 30, loO, 3O0
and even 800 miles away. At present the maxi
mum distance to which Niagara power Is sent Is
twenty miles, but DR.. Bell says that several
plants are now in successful operation else
where which send their supplies of energy to a
distance of one hundred miles
One of the first difficulties encountered in rails
ing the voltage Of a transmission line was TO
make insulators that would stand the strain.
This has been accomplished. Another embar-
rassment incident 10 high pressures is leakage
volts, and even at 10000, the present maximum
in practice the loss is not serious, though II is
clearly perceptible. But DR. Bell says that at
$4,000 or 10000 volts the amount OF energy
which escapes is enough TO prohibit a resort TO
the present method without some change in de-
tails. The wires are now left bare, and are
carried on poles through the air. 1t is possible
that inclosure in tubes, with oil around the cop
per. or burial under ground, might overcome the
tendency TO leak. But II Is TO be feared that
either Of these plans would open up new techni-
cal difficulties. Further experiment is much
needed, therefore, and DR.. Bell wants to see a
structed on sufficiently new principles to serve
as a test The amount Of power thus trans
mitted need not be large. A high pressure can
be obtained in n small steam boiler as we'll
in a big one. The trial might be made, for in
stance, with a plant generating from 1900 TO
1000 horse power.
The suggestion has been offered more than
once within the last few years that even II
Niagara power Is not transmitted TO NewYork
City the metropolis might nevertheless be SINH
larly served from the coal regions. If Pennsyl-
vania's great stores Of fuel were converted into
power before leaving that State, consumers at n
distance might get the benefit Of It Just as
cheaply as now-perhaps more cheaply 1t does
not tax the Imagination severely to conceive Of
this cty's streets being traversed by horseess
vehicles and its atmosphere remaining uncon-
taminated by smoke. The millennium may really
be nearer than most people suppose