THE NEW MACQUARIE LIGHTHOUSE.

Globe, Volume XXII, Issue 1896, 22 March 1880, Page 3

THE NEW MACQUARIE LIGHTHOUSE.

[“Sydney Morning Herald,” March Ist.] The foundation-stone of a new lighthouse at South Head was laid by Sir Henry Parkes on Monday afternoon. The existing lighthouse at South Head is nearly sixty-four years old, the foundation-stone having been laid by Governor Macquarie on the 11th July, 1816. It has answered its purpose well all that time. The following is a general description of the new Macquarie lighthouse and quarters:— The new lighthouse is being erected as close as practicable to tbe present one, and on the western or harbor side of it. The height, dimensions and external features of the present lighthouse will be very nearly preserved in the new one, as being a good, wellbalanced and effective design, and possessing a bold and striking outline, it affords in itself an excellent landmark by day, and no beneficial object would be gained either by altering the original or substituting a new one. The internal arrangements of the building have been modified to a certain extent to meet the requirements of the electric light. The lantern room will contain the dioptric apparatus, lenses, clockwork, machinery, &c., in connection with electric light. The light is a first-order dioptric holophotal revolving white light, with one and a-half minute intervals between the flashes, having all the latest improvements. It will be one of the most powerful lights in the world. The engines that will supply the motive power to the machines are to be * silent horizontal gas engines,’ one to each machine, one engine and one machine producing sufficient light power for fine weather, and two engines and machines coupled together doubling the intensity of the light during stormy, rainy, or misty weather. Gas engines were decided upon to provide the motive power, from reasons of cleanliness, economy, freedom from dust, smoke, &0., and more especially deficiency of a reliable and permanent water supply; also the necessity of making provision for engine, boiler, and wood and coal houses, which would have been entailed by using steam power. The gas being at present as far as Rose Bay from the Sydney Gas Company’s works, no difficulty will be experienced in carrying it to the South Head. It is considered necessary, where the electric light is used, to have an apparatus for an oil lamp always ready for instant application in the event of any accident occurring to the electric light or machinery, and gas being laid on to the building, provision can bo made for the direct substitution of it instead of oil in the case of accident arising. Gas will also in all probability be used for lighting the new keeper’s quarters and for other purposes. The advantages presented by the employment of the electric light as the illuminant are, that with one machine and one engine working, nine times greater intensity of light-power is gained, and when two are used coupled together, the intensity of the light is augmented to eighteen times that of the ordinary oil lamp. The light will have a range of twentyfive miles seaward ( the present one being visible for twenty-one miles), but it will be discernible for a greater distance, owing to the luminosity produced in the atmosphere by the electric beam before the direct rays are visible. The light will bo superior in range and power to any European electric light, the latest of which is that at the Lizard Point, Cornv fcl', England, and which was displayed in the year 1875. Insulated conducting wires are to_ bo carried from each magneto-electro machine,

through a tube out in the centre of the tower wall up to the light-room, and be there connected with the carbons for producing the electric light; the same tube will also contain a gaspipe, having connections with each floor. The gas main will be brought to a gasholder 20ft diameter and 20ft deep, held in a cemented brick tank excavated in the rock to the south of the lighthouse, and containing four or five days’ supply in the event of any repairs or accident occurring necessitating the temporary cutting off the gas from the main. Prom the gasholder pipes will be led underground to the engines. The lighthouse will be constructed of stone obtained from a quarry opened for the purpose between the building and the ocean, and which has boon approved of after considerable search and trials of the various sandstones in the neighbourhood. The height of the tower from tha ground floor to the top floor will be 56ft Sins, and to the centre of the light or focal plates 695 t Sins ; tha height to centre.' of light above high-water mark will be 34Gft. The work was commenced on the sth November, 1879, and the contract time for completion of the work is 15 months. The amount of the contract (including quarters, but exclusive of provision for the electric light) is £11,300.