The Stourbridge Observer, Cradley Heath, Halesowen & District Chronicle.
Stourbridge, West Midlands, England, 1880-01-17 00:00:00

THE ELECTRIC LIGHT IN AMERICA.

The Times of Monday published an interesting letter from
a Correspondent at New York (under date Dec. 30), on the
subject of the Electric Light. We make the following
extracts from the letter :
-

Within the past two weeks Mr. Edison. the in-
ventor, has stumbled upon something which at last
bids fair to solve the problem of the illumination of
dwellings with eleetricity. . . About two months
ago Edison abandoned his platinum lamp altogether
and began to experiment with carbon. He has now
hit upon something by accident which not only
astonishes the public, but more especially himself and
the men in his shops. The most astonished man is
certainly Edison himself.
The shops at Menlo-park, a flag station on the Penn-
sylvania railroad, 60 minutes' ride from New York,
were established four or five years ago. They were
devoted to the manufacture of electrical apparatus,
the perfection of the telephone. the phonograph, the
motor, &c. In the summer of 1878 experiments began
to be made with the electric light. Edison supposed
at first that the whole battle was won when he had
found a plan to divide the electric current. He
adopted for a lamp a coil of platinum wire, and en.
deavonred to perfect a regulator of the current which
would allow the coil to become luminous without
becoming so hot as to melt. He laboured diligently to
perfect this device until about two months ago. .
Weeks and months of costly experiment with this idea
followed. . . . The experts forsaw failure long before
Edison did; and, finally, Edison himself reluctantly
came to the conclusion last fall that he was on the
wrong track entirely. The man wore himself out very
nearly, and the disappointment almost sent him to his

grave.
About two months ago the inventor resolved to test
the utility of carbon. He was determined not to stir-
render until that had been done. What inspired him
to make this departure was a trivial incident. One
day he was busy with some lamp-black and tar, with
which he was making some wafers for a telephone.
Happening to rub some between his fingers, he found
he could draw it out into a thread. The thought came
into his mind, "Why can I not make a carbon wire
for an electric lamp?" After a little consideration, he
began a series of experiments in this direction. He
found that he could easily make a carbon wire,
as had occurred to him, and that a burner for
a lamp could be made from it. After several weeks
of effort, he found that a carbon wire, enclosed in a
hermetically sealed glass globe, from which the air had
been exhausted, would do well for a eisort time. It
made a good light, and was satisfactory in that re-
spect, but it was not durable. Invariably it was soon
consumed. He then thought of the idea of taking a
simple cotton thread, carbonizing it in a retort, and
making coils out of that. All sizes of thread and
twine were tried. But even this material would not
do. The texture of the carbonized thread was too
loose. The material was betterithan lampblack and
tar, but was not good enough. Then Edison tried
common paper. He cut out thin strips of various
kinds of paper, which he carbonized as before, by lay-
ing them between sheets of tissue paper, enclosing
them between cast-iron plates, and subjecting them to
intense heat in a muse furnace. The slips were cut
out in the form of a horseshoe. One of these slips,
made from Bristol board, was enclosed in a vacuum (ti
that be a proper expression) in a glass globe, the electric
current being conducted to and from it by means
of platinum wires. This was three or four weeks
ago. The lamp thus made was tried. The horse-shoe
of carbonized paper became incandescent, and gave a
beautiful mellow light, equal to that of one gas-
burner. It did not consume, and it lasted very well
during the first day of experiment. Next day the
same lamp was tried again. It belurted beautifully
somewhat to the surprise of Mr. Edison and his as-
sistant. Both men now became very much interested.
They instructed their glass-blower to make several
lamps with great care; the pump perfected by Crook
and Sprengel was used to exhaust the air from the
globes; and particular attention was paid to the
matter of sealing the stems of the globes (which was
done with a blow-pipe). About two weeks ago experi-
ments began with these lamps. They all behaved well,
and a few days more served ta show that a valuable in-
vention had finally been evolved from the busy brain of
the philosopher of Menlo-park. In fad, the lamp
appeared to be complete.
A whole crop of new questions now sprang into view,
one of them being the durability of the new style of
incandescent carbon under strong current. This ques-
tion was readily disposed of. One lamp was raised
to a power of 30 gas-burners with perfect safety, and
the capacity of the paper carbon to withstand an
intense current appeared to be proved. As it is not
the intention of Mr. Edison to make lights for dwel-
lings of greater power than one or two gas-burners, he
considers that this part of the problem is disposed of.
If a burner can be made to give the light of 30 gas.
burners with safety, it can surely be relied upon to
give the light of one or two. Then came up another
question. Ten lights could be maintained in the labo-
ratory with the expenditure of one-horse power, or
eight net in a dwelling. In practical use the cur-
rent would be turned off and on suddenly. Would
not the sudden turning on of a current of elec-
tricity, equal to one-eighth of one horse-power,
rupture the carbon in time? One-eighth of one-
horse power will drive several sewing machines, and
when administered in the form of a blow is all a man
would ever wish to have applied to his person. One
of the men in the shops was detailed to turn on and off
the current of electricity at one of the lamps. The
man did this 5,000 times, which would be about the
number of times that a lamp would be lighted in a
dwelling in the course of ten or twelve years. The
lamp withstood this test perfectly. Various other
questions came up and were promptly solved in the
same manner by actual experiment. The state of
feeling which reigned in the shops at Menlo-park as
Olney IVAIJCIII....tu %fa, CS
the lamps sustained every test, can better be imagined
than described. Every man, from Mr. Edison down,
was first astounded and then exhilarated. They have
had so many failures that they can now scarcely
believe their senses.

There are now forty-five lamps lighted every even-
ing at Menlo-park, and the number is being increased
as fast as the lamps can be made. Two or three of
the dwellings in the village have been supplied with
them, and a dozen or more street lamps along the road
leading to the railway station have also been furnished
with them. The others are in the shops. One of the
latter has now been in use day and night for fifteen
days, and is as good as when first put into operation.
The invention of this new lamp has not produced
any very striking effect in regard to gas stocks here
yet. Scepticism in regard to Mr. Edison's achieve-
ments is too strong yet. But a very decided effect has
been produced with reference to the stt.ck of Mr.
Edison, s Electric Lighting Company. There are 3,C00
shares in the capital of the company, the par value of
each being 100 dole. This stock was down to 20 dols.
a share last summer, and a large number of the present
holders bought at that price, The rise in value during
the last two weeks has been enormous. • There
has been nothing like it in the history of stocks in
New York city. Very few large holders of shares
in the Edison Company are now willing to sell at
3,500 dole.; and the majority of the small holders are
demanding and waiting for 5,000 dole, a share. The
stock may never go to that height, because experiment
may develop defects in the new lamp not yet ob-
served; but the feeling in the company now is one of
perfect confidence that the problem of household
illumination has been solved, and higher quotations
are predicted by them. The company is composed
of merchants and bankers of high standing, and few
of them are willing now to sell out except for very
great inducements.
Mr. Edison himself does not indalge in extravagant
assertions. I had a long talk with the inventor to-
day, and went with him all over the shops, learning
every detail of construction of the lamps and exam-
ining the generators, air-pumps, furnaces, motors, and
other apparatus. Mr. Edison makes no predictions,
but says that he is going on until he has 150 lamps of
the new pattern burning in the dwellings and streets
of Menlo-park. It is his own teat of the merits
of the new lamp, the object being to develop defects.
A few weeks from now he will be able to formulate
a clear opinion about the merits of the invention.
Wires are meanwhile to he run down to tne village
of Rahway, four miles distant, in order to teat the
difficulties of distributing the maths and lamps over
a large area. Until the data afforded by the whole of
this test are collected Mr. Edison will not declare his
final opinion about this matter. He believes, how-
ever, that the new lamp can be distributed over a
large area, and houses lighted therewith, for the same
price as now paid for gas, possibly less but of the
latter he is not certain. The lamps are 41n. high, are
simplicity itself in construction, and will c3st to con-
struct only 25c. apiece