C. NEW SOUTH WALES LIGHTHOUSES. 



7. Alternating lights of different colours, generally white and 

 red alternately. 8. Double lights. 



Revolving Gear for Lighthouse Apparatus. 



This is a clockwork motion, the motive power of which is a 

 heavy weight suspended and working through a wrought iron 

 tube in the centre of the tower. The cage itself revolves upon 

 and is supported by a roller base, consisting of a series of small 

 rollers, kept equidistant, which revolve round the centre, and on 

 their own spindles, thus reducing the friction to a minimum. 

 The gear is fitted with a governor to regulate the speed of rota- 

 tion, and is of the conical pendulum centre weight type. The 

 centre weight consists of a metal disc connected to the governor 

 arms, and the lift and speed is regulated by two set screws pro- 

 jecting from the main framing. The motion can also be stopped 

 at any time by means of a similar set screw which can be made 

 to press on the edge of the disc. The weights, which are sus- 

 pended by a pulley from an endless chain, are wound up periodi- 

 cally according to the speed of rotation of the cage, the act of 

 winding having no effect upon the revolving gear. In case 

 of accident or repair to the gearing, the cage can be discon- 

 nected and caused to revolve by manual power from a winch 

 handle. 



Cost. 



The total capital expenditure on the Lighthouses up to the 

 present has been about £200,000, and the present annual cost of 

 attendance, stores, &c, about £11,500. The total expenditure 

 on repairs and maintenance and additions during the last forty 

 years has been £24,000. 



The design, construction, maintenance and repairs of the Light- 

 houses were originally under the Colonial Architect, Mr. Barnet, 

 but were transferred to the Harbours and Rivers Department in 

 1889, and placed under Mr. Cecil W. Darley, M. Inst. C.E., 

 the present Engineer-in-Chief for Public Works. 



