PLAN OF KARORI ROCK LIGHT.

Dominion, Volume 6, Issue 1704, 22 March 1913, Page 6

PLAN OF KARORI ROCK LIGHT.

CONCRETE TOWER. INGENIOUS AUTOMATIC BEAM, . \ Arrangements for the erection of a lighthouse on Karori lloek are now well in hand. Tho construction of the tower will bo commenced at an early date, and the light has b<?eu ordered. Mr. G. Allport (Secretary for Marine) informed a reporter that the light which had been selected was tlio "Aga" acetone acetylene light. It is manufactured by a Norwegian firm, and is being obtained by the Department through Melbonrno agents. The Karori Rock light will have 11 range of about fifteen or sixteen miles in clear weather, and will ba visible at that distance from a vessel's deck. It will be feimilar in character to the light which stands 011 Diefl'cnbach Point, at the Picton end entrance ito Tory Channel, but of greater power. 1 Tlw tower is to be of ferro-concrete. It will be erected for tho Marino Department under the control of Mr. It. Fraser, tho Department's lighthouse inspector. Much of tha material for tho concerto is obtainablo close at hand, but the work will be difficult, as it can be carried on only 111 good weather, Mr. Fraser is at present engaged upon the Chickens Light in tho Hauraki Gulf, and as soon as it'is completed, will undertake UlO work at Karori Rock. The acetone acetylene light, • Mr. Allport stated, is coming into very general favour. The illuniinnnt is oomprcssed acetylene 'gas, contained in cylinders, which are obtainable from a firm in Napier, and also from the Melbourne agents, who are .supplying the Karori Rock light.. The' light is automatic in its operation, and can bs left unattended for periods corresponding to the number of cylinders with-which it is furnished. It is anticipated that the Karori Rock light will only' have to bo visited, in normal circumstances, once in two months: .

Tile light is not left to blazo .wastefully in the' daytime. By an ingenious automatic device the action, of ordinary light reduces tho volume of the ilnmo in tho lantern until only a pilot-light remains burning in the daytime. Bright sunlight is not necessqry to ensure the successful l working of; this apparatus. Ordinary light, even 'on a dull dav, ■suffices. A light of this character is in successful operation on Beam' Rock, in Auckland Harbour, and another is beiug installed at tho Chickens, in tho Ilauraki Gulf. Mr. Allport remarked that hundreds of thcra lights were now iri it?s in different parts-of the world, and that reports as to,their working were entirely satisfactory. The Karori Rc-ek light in any cara will be visibla over a wide stretch of land and pea, and in tho unlikely event of its failing to net, th'e failure would be quickly reported. Concrete has b;en solected as, the niaterial for the tower, in preference to iron, because plenty of gravel and sand are obtainable on the adjacent coast, and 'because the concreto structure will last much longer.