The daily Cairo bulletin. (Cairo, Ill.) 1878-1???, 1879-07-09
LONDON LETTER.
THE REPORT OF THE ENGLISH PARLIAMENT
COMMITTEE on THE ELECTRIC LIGHT.
From our Regular Correspondent

i'"Hi Oui ivE u!ur correspondent,
LONDON, June 81, 1879.
The report Of the select committee of the
house Of commons on electric lighting was
issued yesterday. II states The general
nature of the electric light has been we'll
explained in the evidence of Professor Tyn-
dali, Sir William Thompson and others. 1t
is an evolution Of scientific discovery
which has been IN active progress during
the whole Of this century. Essentially the
electric light is produced by the transfer
nation of energy either through chemical
or mechanical means. The energy may be
derived from natural force, Gs for instance
a waterfall, or through combustion of q
material in the cells Of voltaic battery,
or OF fuel ina furnace. The energy being
converted into an electric current may be
used to manifest electric light by passing
between carbon points, or by rendering in
candesent solid bodies, such as iridium.
A remarkable feature Of the electric light
is that it produces transformation Of en-
ergy in a singularly complete manner.
Thus the energy Of one-horse power may
be converted into gaslight, and yields a
luminosity equal to twelve-candle power;
but the same amount Of energy transformed
into electric light produces 1,G00-candle
power. 1t is not, therefore, sur
prising that while many prac-
tca witnesses see serious
difficulties in the speedy adoption Of the
electric light to the useful purposes of illu-
miration, the scientific witnesses see in
this economy of force the means of great in
dustrial Development, and believe that in
the future it is destined TO take a leading
part in public and private illumination.
There is one point on which all witnesses
concurrcd, that its use would produce little
OF that vitsted air which is largely formed
by the products of combustion of ordinary
iilumlnants. Scientific witnesses also con
sidered that in the future the electric cur
rent might be extensively used to transmit
power as well as light to considerable dis
tances, so that the power applied to me-
chanical purposes during the day might be
made available for hight during the night.
The committee only meation these opinions
as showing the Importance Of allowing full
Development to practical application Of
electricity, which is believed by competent
witnesses to have future important bear
ings on industry. So far as the practical
application Of the electric light has already
gone, there seems to be no reason to doubt
that il has established itself for lighthouse
illumination, and is fitted to illumine large
symmetrical places, such as squares, public
halls, railway stations and workshops. It
is used in Paris for lighting shops which
require light by which different colors
may be distinguished, and has recently
been used in England tor the
same purpose with satisfactory
results, Many trials have been made for
street illumination with greater or less sue
cess. Compared with gas, the economy
for equal illumination does not yet appear
to be conclusively established Although
in some cases the relative economy for
equal candle power is on the side the cleo
trio light, yet in other cases gas illumina-
ton of equal intensity has the advantage.
Unquestionably, the electric light has not
made that progress which would enable it
in its present condition to enter into general
with gas for the ordinary pur-
poses Of domestic supply. In large build
lngs the motors necessary to produce the
electric light may be readily provided; but
50 far as we have received evidence, no sys.
tenn Of central origin and distribution suit
able to houses Of moderate size has hither-
to been established. The committee do