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ELECTRICITY. 



light ; but the importance of the question, rel- 

 ative to the general administration of light- 

 houses, is much less than was at first supposed. 

 In 1863, in a notice of the applications of the 

 electric light, the author suggested the lighting 

 of vessels by it. The maritime exhibition at 

 Havre shows that the suggestion has been con- 

 sidered, at least in principle. In the point of 

 view of lighting the course of a ship, no one 

 will deny that the oil lantern is insufficient to 



Erevent collisions at night ; while the electric 

 mtern would illumine the air all around, and 

 the rocking of the vessel would cause such 

 changes of light as would attract the notice of 

 the men on other vessels. When the whole 

 cost of a ship is considered, that of electric en- 

 gines is insignificant ; two or three horse-power 

 will work a magneto-electric machine. And 

 the electric light will serve other purposes on 

 board a ship. Recent experiments have shown 

 that it would be possible to assist a ship in her 

 course by dazzling the steersman by a jet of 

 light, when an oil lantern would not be seen 

 by him. It can also be used to light under 

 water ; an application that concerns the repairs 

 of the sheathing and hulls of vessels, the find- 

 ing of lost articles, and the catching of fish. 

 The fish are confused by the light, and then 

 easily caught. Mons. Dubosc has constructed 

 a lantern well fitted to enclose an electric lamp. 

 The conducting wires are connected so that 

 there is no chance for water to leak into the 

 lantern. This apparatus can, without fear of 

 too high pressure, be lowered to great depth 

 in the sea. (Translated for Van NostrancPs 

 Engineering Mag.} 



The London Chemical News states that the 

 electric light at Dungeness can now be worked 

 by either of the two engines, so that no dis- 

 turbance occurs when one requires repairs. 

 The services of the high-class engineers and 

 firemen have been dispensed with, and the 

 Elder Brethren have their own ordinary keep- 

 ers trained to drive the engines as well as to 

 attend to the lamps, a steady, old, experienced 

 keeper being placed at the head of the estab- 

 lishment. Since the alterations made at Dun- 

 geness, the light there has worked with great 

 regularity and efficiency, and the Elder Breth- 

 ren have proposed to place similar lights at 

 the South Foreland, Lowestoft, and Souter 

 Point. The English Board of Trade approve 

 the extension of this mode of illumination to 

 the South Foreland and Lowestoft, but sus- 

 pend their decision respecting Souter Point. 

 The committee of Elder Brethren who attend- 

 ed the Paris Exhibition say, that so far as the 

 eye is a test, the power of the English fixed 

 light was considerably in excess of the French, 

 and when both machines were in use, and 

 there was a good current, the fixed beam of 

 the English light did not contrast unfavorably 

 with the revolving one of the French, the flash 

 of which is of great power. The contrast of 

 the electric fixed light with the French first- 

 order oil dioptric revolving light was very 



marked; indeed, the one may be said to put 

 the other out. But the most beautiful feature 

 of the electric was the extraordinary beam it 

 gave. It shone night after night, large, steady, 

 and lustrous as a planet, and you could see in 

 the darkness a beam passing as far as the eye 

 could see. From the tower, with the light at 

 the back, it was very marked, and quite lit the 

 hills round Paris. The whole horizon in the 

 plane of the light showed the white beam, and 

 at the distance of four miles it shone upon the 

 windows of some houses, making them appear 

 to be lit up. By extinguishing and relighting 

 quickly several times this was very plain. Alto- 

 gether the light was very remarkable, and the 

 committee were glad to be able to report such 

 an advance as the powers of the light show 

 over that at Dungeness; indeed, the latter 

 gives to the observer no conception of what 

 the present one is; and it is satisfactory to 

 know that the result of five years' work and 

 observation, with imperfect and ill-arranged 

 apparatus, has now borne such good fruit ; and 

 that as England was the first to test and adopt 

 this adjunct to the sources of light-house illu- 

 mination, so she still retains her superiority. 

 It is due, however, to Mr. Holmes to say that 

 great as are the improvements already effected, 

 he states that he is confident he can yet great- 

 ly increase the illuminating power before the 

 present apparatus is reerected at a permanent 

 station. 



Satisfactory experiments have been made 

 with the electric light on board the French 

 iron-clad ship Heroine and the yacht Prince 

 Jerome, to ascertain the value of the light for 

 signalling purposes. The machine was fur- 

 nished by the Alliance Company, producing a 

 light equal to two hundred Carcel burners, or 

 sixteen hundred candles. An ordinary newspa- 

 per could be read in the direct line of the light 

 at the distance of 1,531 yards. Signalling was 

 most easily done by short and long flashes, and 

 was found to be practicable. The Government 

 commissioners reported, after an investigation, 

 that the apparatus showed a very powerful 

 focus of light, perfectly suited to night signal- 

 ling, or for throwing a light over a coast or a 

 ship ; and that it would be most useful on board 

 the flag-ship of a commander-in-chief. By the 

 aid of this light, the Prince Jerome was enabled 

 to steam by night through the intricate navi- 

 gation of the Bosphorus, when the yacht be- 

 longing to the Viceroy of Egypt was obliged 

 to wait until daylight. On some steamers of 

 the French commercial marine the same light 

 produced by the magneto-electric engine, has 

 been introduced, and is regarded as a practical 

 success. 



Experiments in Electrolysis. M. Bourgoin 

 has published a memoir on the electrolysis of 

 organic acids and their salts. He has found by 

 experiment that the action of the electric fluid 

 is in reality only a fundamental action on all 

 acids and salts, whether mineral or organic. It 

 separates the basic element which goes to the 



