THE GALLEY HEAD LIGHT.

New Zealand Times, Volume XLII, Issue 7111, 10 March 1884, Page 4

THE GALLEY HEAD LIGHT.

A short time since Mr J. Henderson, the secretary of the British Shipmasters’ and Officers’ Protection Society, was requested to inspect the new light erected on Galley Head, and to report on its character and power to the Society, the subject of lighthouse illumination at the present time occupying much attention. Mr Henderson visited the light on November 10, and has just presented his report. He speaks of the Galley Head Light, which is the largest in the world, and one of great efficiency and immense value to seamen, and, describing its character and power, says :—“ The light is group-flashing. A great beam is transmitted by annular lenses to the horizon every minute, and this beam, as it passes the eye, is broken up into a group owing to the momentary extinction and re-ignition of the light. The apparatus consists of thirty-two lenses, four tiers in height, and eight in each tier, the whole forming on octagon about. 13ft high. The size of each lens is 3ft IJih high, and 2ft sJin in breadth. The lenses are made in concentric rings, each circle being bevelled and ground according to the angle from the light. The lenses are of French manufacture. The light is produced by gas, there being four burners, containing sixty-eight jets each, of 1253 candle power, 272 jets in all, being an illuminating power of 5012 caudles. The flame produced is optically about 13ft high, and equal in strength to 1,090,000 candles.” It is the largest light yet erected, produces a truly glorious illumination, arid possesses an amount of surface for illuminating haze and fog, which renders such a light of inestimable value to the mariner. The effect of the four burners acting through this great surface must be such that “when heavy fog prevails it may be quite possible for a seaman to observe the action of the groups on the fog when he may be quite unable to distinguish the direct beam from the lighthouse. In fine weather only one burner is used, but in case of thick weather, as the visibility diminishes, the others are lighted as required. The method adopted for extinguishing and re-igniting the gas for producing the flashes is exceedingly ingenious.” After explaining that there are five retorts, one only being required to produce the gas for consumption, that there are two gasometers for storage, and that the gas is extracted from cancel coal, Mr Henderson points out that in case of anything going wrong with the gas, provision is made by which the usual Trinity oil lamp can be applied in less than half a minute,- and concludes by acknowledging the courtesy he had received from Mr J. 11. Wigham, of Dublin, the constructor of the light, and by observing, “In my opinion gas illuminants areas yet in swaddling clothes, and, if in their babyhood they have done such things as at Galley Head, and are likely to do still more at Mew Island (where a remarkably powerful light is to be erected), what may we expect when maturity is reached 1” 1