The Stourbridge Observer, Cradley Heath, Halesowen & District Chronicle.
Stourbridge, West Midlands, England, 1878-11-09 00:00:00

THE WERDERMANN ELECTRIC
LIGHT.

The Times of Monday gives the following :

"Another practical advance in the development of
the electric light was demonstrated to a number of
scientific gentlemen and others who assembled on
Saturday afternoon at the works of the British Tele-
graph Manufacturing Company, 274, Euston-road,
London. The object of the gathering was to witness
the first public exhibition of M. Werdermann's electric
light, by which the current is made divisible so as to
be readily applicable to a number of lamps on the
same circuit. To effect this object M. Werdermann—
whose name is not unknown in connexion with elec-
tric lighting—has departed from the track more or
less generally followed by investigators in this
direction, and has worked in a path which, so far
as we are at present aware, is quite his own, although
it may be that the Patent-office will in time reveal the
same idea as evolved from another brain, so numerous
are improvements, real or fancied, in electric lighting.
becoming, and so rapidly are thy following upon each
other. M. Werdermann does not deem it as essen-
tial that a certain definite interval should exist
between the points of the carbon electrodes used
in producing the electric light. He therefore
discards the electric arc space, and places his
carbons in actual contact and produces a good steady
light. In the place of the usual carbon rods
meeting end to end, M. Werdermann has but one rod
which is pointed and impinges upon the face of a disc
of carbon forming the negative of the lamp. The disc
is placed at the top of the lamp and is about 2in.
diameter, and lin. thick, the under side being convex.
It is held in a ring frame carried by a hinged arm,
which is attached to the lower portion of the lamp
standard. The carbon rod is rather more than one-
eighth of an inch in diameter, and may be of any rea-
sonable length. It is held vertically under the disc in
a guide or collar, and its lower end is fitted in a small
cap or holder, to which a pair of fine cords are at-
tached. These cords are led up over pulleys and down,
again to a counterbalance weight, and as the carbon is
free to move in its collar, its point is always held up
gently against the underside of the carbon disc. By
this means the consumption of the carbon rod is
uniformly and easily followed up. The consumption
of the disc appears to be practically nil judging from
the appearance of those used on Saturday. They were
stated to have used up a number of pencil carbons
during M. Werdermann's protracted investigations
and experiments, but they were only marked by a few
spots where the positive carbons had impinged upon
thew. There were ten of these lamps tested on Satur-
day in one cireuit.
The machine used for supplying the current of
electricity to them was a small Gramme continuous
machine such as is ordinarily used for electro-plating.
It was stated to be capable of producing an electro-
motive force of about four Daniell cells, the intensity,
therefore, being low, but the quantity large. The
machine was driven through belting by a small engine
used to drive some of the machine tools in the com-
pany's fitting shop. A conducting cable was laid on
from the machine to the row of lamps, and from it
ten wires were led up, one to each lamp, resembling
in its arrangement a gas main with its supply pipes.
The current produced by the machine is led along the
main cable and through the supply branches to the
lamps, passing through the positive carbon of each,
and then through the disc or negative carbon, and so
away by a return cable back to the machine. Al-
though constructed upon a practical scale, the lamps
are more or less experimental, being the first M.
Werdermann has made. They, however, illustrated
the principle exceedingly well, giving a steady, though
small light of very good colour and of moderate inten-
sity. The divisibility of the light was clearly demon-
strated, as was the power to extinguish and re-light one
or any number of lamps in the series without affect-
ing the remainder, except to increase their intensity.
This increase of light will be prevented in the lamp
which M. Werdermann has designed for practical use,
and which contains the means of controlling the unused
current. One of the points aimed at by M. Werder-
mann is the production of a light which shall not re-
quire any intercepting media around it to tone down
its rays, such as coloured or opaque glass, which he
maintains robs the light largely of its illuminating
power. The construction and general arrangement
of M. Werdermann's system is devoid of all com-
plication, and as far as the experiments of Saturday
went its working was very satisfactory. During the ex-
periments two lamps of similar construction, but of large
size, were tried with equally satisfactory results. With
regard to tile cost of producing the light and the photo-
metric value of the light itself we can say nothing,
inasrunch as the machine was driven from an engine of
far higher power than it would of itself require, and
there were no means of ascertaining the value of the
light photometrically. In comparison with the ordinary
gaslights in the shop it was, of course, most brilliant
and pure' colours coming out perfectly. These points,
as we have observed before now, must be left for
time and practical application to determine. For
the present, we can only say that M. Werdermann has
succeeded in dividing the electric current in a simple
manner, and in producing a steady light—necessarily
of small power because of the smallness of the pro-
ducing apparatus—but which is capable of being in-
creased as the productive power is increased. Neither
can we speculate on the number of parts into which
the current is divisible under M. Werderraann's sys-
tem—or, in other words, the number of lights he can
produce from one current—as this is subject to these
and other governing conditions. We should add that
the Werdermann light is being introduced by Messrs.
J. Berger Spence and Co., of 31, Lonatnrd-street,
London."

On the subject of "Gas v. Electric Light," The
Times of Saturday publishes the following letter from
C. Meymott Tidy, M. 8., Professor of Chemical and
Forensic Medicine at the London Hospital, Medical
Officer of Health for Islington, and late Deputy
Medical Officer of Health for the City of London, &c.
48, Queen Anne-street, London :
Sir,—Gas v. Electric Light" is a cause just now being tried
before a public tribunal.
The questions of vested interests, value of gas shares, and
the like, unfortunately, do not concern me. Allow me, there-
fore, as an independent witness, to say a few words in the
cause under discussion.

One advantage of a gas flame is that it can be easily regn•
lated—in other words, turned up or down as required. The
electric light, on the contrary, cannot be turned down, for,
reduce it to its minimum, you still have a light of 370
candles, to quote a very low estimate, and oce that my own
experiments would not Justify me in adopting.
_

Nature has ordered that darkness ana light should alter-
nate. We may some day have to revise the authorized
version—" The sun knoweth not his going down, nor the
moon her rising."

Again, the electric light practically issues from a point,
the gas flame from a surface of sensible magnitude. Hence,
in the former case, the intensity of the shadows. Surely this
alone unfits it for use as a room illuminant. Tnere is a
remedy, I admit. That is you may have two electric lights.
But this means twice 370 candles. And if one electric light
be too much, ctforttori two are.

. _
The electric light is peculiar in its composition. It con-
tains an enormous quantity of the blue and violet rays of the
spectrum and of rays beyond the violet. These rays are
the chemical rays—that is, they are the rays endowed
with intense chemical activity. The gas flame is very
wanting in these rays. Photographers know that a small
gas flame in their dark room is practically inert on their
sensitized plates ; while, if but a single ray of the electric
light were admitted all their work would be destroyed. To
use a scientific phrase, the electric light is remarkable on
account of its "actinism."

These facts have a practical bearing. I have made a point
of remaining in the neighbourhood of the electric light for at
least three hours in order to observe its effects upon me
after being exposed to its action for some time. For a time
nothing struck me except the intensity of the illumination
and darkness beyond. But, before long, my eves became en-
tirely blinded to all rays except the blue; and, as a result,
everybody and everything appeared of a ghastly blue tint.
For hours after I returned home the blue rays haunted me;
but, what was worse still, I suffered from what I am rarely
a sufferer from—an intense headache, especially related about
the region of the eyes.
As a medical man, I am convinced that whatever may be
the advantage of the electric light as an illuminant for
large outdoor spaces, it can never be used as a room illu-
minant, or even as a general street illuminant with advan-
tage, save to the medical profession generally and to oph-
thalmic surgeons in particular.

The trial of the electric light in the Royal Arsenal, Wool-
wich, has encouraged the authorities to fix a second lamp in
the same werkshop as the first, which is that used by the
carpenters employed in the Royal Laboratory Department.
The supply of electricity to the two lamps is provided by
separate machines attached to the shafting, by which the
lathes in the manufactory are driven, and the light thus
furnished is ample for the illumination of the whole work-
shop, which is about 100 ft in length by 501 t. wide. A similar
experiment is to be made in the Royal Carriage Department
in the Royal Arsenal, Woolwich. A large and lofty shed
built of corrugated iron, and known as the mounting ground,
which at present is very badly lighted with 150 gas jets, is to
be furnished with two electric lights, but the area being con-
siderably larger than that of the laboratory workshop, it is
questionable whether these two will be sufficient. If not, a
third lamp will probably be added.