Lighting by Electricity.
As many of the fires which occur in this country have their origin in the careless and imperfect means used for lighting stores, factories and dwellings, the following account of the practical application of the electric light used in numerous factories in France will be read with interest. We condense it from the London Journal of Applied Science:
It seems that a number of factories in Paris, Rouen, Oaours, and other French cities, have the new system of lighting in successful operation, and in every instance its use is welcomed as a great improvement both as regards the light itself and the safety secured. In a wool spinning factory at Daours the electric light has been in use for more than a year. The building is 140 feet long, 35 feet wide, and has a twelve feet ceiling. This “tciling is composed of planks and laths, and is, like the walls, lime-washed. The electric light is supplied by two lamps placed at a height of six feet from the floor, and thrown upon the ceiling by means of conical reflectors, which prevent the diffusion of any direct light whatever. The deflected light is reflected and diffused in all directions from the ceiling and the walls, and without shadows. The light is much superior to that given by ordinary gas ; it is soft, and at once local and general in all parts of the work. The foreman, seated at his desk, has plenty of light for working at his books, and sees all over the building ; thus the grand intensity of electric light is at once utilized and moderated. The machinery is at one end of the factory, and is driven by a belt from a water-wheel. The cost of these two lamps, apart from the machine, is only about four cents an hour, and they more than supply the place of the seventy gas jets by which the factory was formerly lighted at an expense of forty cents an hour.
Without mentioning the other advantages of this kind of lighting in factories, it is enough for our present purpose to call the attention of underwriters and mill-owners to the manifest security from fire afforded by a single light which will supply the place of from fifty to seventy-five gas jets or kerosene abominations, especially as no matches or hand lamps arp required, and the light itself is completely enclosed in glass lanterns. A practical point in this connection is the fact that the French insurance companies have set their approval to the new invention by reducing the rate of insurance on factories thus lighted by electricity.
Perhaps the importance of the subject demands that we should quote the concluding paragraph of the article in the Journal of Applied Scienee to which allusion has been made :
“These facts compose a strong case, and the success which has been obtained is easily ascertained. A perfect light, as regards colors, which neither injures the eyes of the workpeople, nor renders factories unhealthy by contaminating the air, while immensely reducing the risk of fire, and which saves seventy-five per cent on the cost of gas lighting, possesses so many advantages that it is only surprising that the manufacturers are not more eager to accept it at once. The experiments in the electric lighting with the Gramme machine are now daily repeated at the Palais de l’lndustrie, in Paris. An area of 12,000 square yards is lighted by two electric lusters of six lamps each, suspended at twenty-seven yards from the ground. The power is supplied by two steam engines of twentyfive horse-power each. It would take 10,000 candles to yield an equivalent light on the floor, 300,000 to illuminate the whole space as thoroughly. At first there was but a single luster; they then used two ; and it is proposed soon to introduce three. It is understood that during the International Exhibition there will be tests made of the various methods of lighting streets and buildings with electricity, and the relative value of the different systems will be determined.”