Democratic Sentinel, Volume 18, Number 7, Rensselaer, Jasper County, 2 March 1894 — LARGEST LIGHT-HOUSE. [ARTICLE]

LARGEST LIGHT-HOUSE.

t Ison the French Coast and Is of Wonderful Power. If there is one thing which the French Goteminent has endeavored to do well it has been to warn mariners of dangerous parts of the French coast, and if there is a spot where the Service des Phares de France has largely experimented with a view to providing the best method of lighthouse illumination it has been at the light-house at the Cap de la Heve, near Havre. Four different kinds of apparatus have already been tested at this light-house, which are described in the Pall Mall Gazette. The first comprised oil lamps with reflectors giving luminous intensity of 8,000 candle-power, visible in clear weather a distance of forty-one miles. In the second case oil lamps were used with fixed lenticular apparatus, yielding a candle-power of 19,000, capable of being seen in clear weather a distance of forty-nine and one-half miles. The third comprised the employment of the electric arc light, with fixed lenticular apparatus, giving an illumination of 24,000 candlepower, the light being visible fiftyseven miles away. In the fourth case the use of the electric arc light was combined with a lenticular flashing apparatus, yielding 24,000,000 candle-power and capable of being seen on a clear night no less than 130 miles distant. A new light has, however, been practically completed at this light-house, and will give a luminous intensity of 40,000,000 can-dle-pow’er, and it will be the most powerful light-house in the world. As far as the electrical apparatus is concerned, the old magneto machines have been dispensed with and four new generating machines have been substituted. These are two continuous-current dynamos, giving each from twenty-five to forty-five volts. The current yielded by these machines will be utilized for producing light In Serrin regulating lamps, fitted with cylindrical carbons. The optical apparatus which has replaced the old fixed lights is a new type, devised by M. Bourdelles, one of the chief engineers of the Service des Phares, and who was a prominent member of the recent International Maritime Congress held in London. This apparatus gives white flashes, which succeed each other every five seconds, and it possesses this peculiarity, that the number of lenticular panels, which in light-houses of the first order range from eight to sixteen, has been reduced to four. The difficulty of revolving the panels at the necessary rapidity to produce the flashes at sufficiently regular intervals has hitherto prevented the realization of this important improvement, but this now has been overcome in an ingenious manner, and it is now possible to make a complete revolution in twenty seconds, as compared with a minimum of four minutes with the ordinary lights of the first order. The square lantern has been demolished and a circular one substituted. The new light will, as already mentioned, be the largest light-house light in the world. During eleven months of the year the light at the Cap de la Heve will be visible from its geographical bearing a distance of twenty-three miles, while with the old lights this limit has only been obtained for eight months in the year, leaving out of consideration the greater luminous intensity obtained with the new apparatus.