WILLSON GAS AND WHISTLING FLOATING LIGHT OFF EGG ISLAND, NOVA SCOTIA.
THE WILLSON “OUTER AUTOMATIC,” HALIFAX, NOVA SCOTIA.
The maintenance charges are guided by the local market values of materials and labour, the item of repairs and renewals being practically negligible. So far as oil consumption per month is concerned, this fluctuates according to the type of lamp used, ranging from 11/5 pints per twenty-four hours, or 4·8 gallons per month, in the case of a 11/8-inch single-wick burner, to 2¼ pints per twenty-four hours, or 8¾ gallons of oil per month, in the case of the latest 15/8-inch duplex-wick burner. American petroleum-oil, of a specific gravity of about 0·795, gives the best results and the brightest and clearest flame. Russian and other heavier oils generally used in lighthouses are unsuitable. In view of the world-wide operations of the Standard Oil Company, however, no difficulty is experienced in procuring adequate supplies of this oil anywhere between the two Poles.
The oil used in the float cylinder, as mentioned previously, is quite distinct from the burning oil, and is used only to support the float to which the wick is attached. As the oil escapes through the drip-valve, it may be allowed to run to waste, or, what is far preferable, it may be caught, filtered, and used again for this purpose, to bring about a reduction in the cost of upkeep. The float cylinder of a thirty-one-day light, irrespective of the number of wicks, requires the same quantity of oil for the float cylinder—9½ gallons.
The advantages of the unattended, automatic light have been appreciated by the various maritime Powers, and their application is being developed rapidly. They are inexpensive in first cost, and their maintenance charges are very low. In Sweden a second-order light, consuming 6 cubic feet of acetylene gas per hour, throwing a fixed white light of 4,000 candle-power, and visible for seventeen miles in clear weather, costs about £15, or $75, per annum; while the smaller lights, with a 300-millimetre lens and a 12-inch burner emitting 360 candle-power, may be run for £2, or $10, per annum, the low cost in this instance being attributable to use of the Dalén flasher and sun-valve.
The cost of the acetylene gas averages ¾d., or 1½ cents, per cubic foot, a result attributable to the fact that Scandinavia is the world’s largest producer of carbide of calcium.
The Wigham petroleum system has proved similarly economical and reliable, and has been installed in some of the wildest corners of the globe. The Congested Districts Board for Ireland have established a number of these beacons on the rugged west coast to assist the fishermen in making their harbours at night. Many are placed in very exposed positions on headlands, where they are frequently swept by the full force of the Atlantic gales. The Austrian Government has adopted the principle for lighting the dangerous coasts of the Adriatic near Trieste, while the shoreline of Jamaica is safeguarded by more than sixteen lights of this type. Many of these lights suffered severely from the effects of the earthquake which overwhelmed the island a few years ago, but others withstood all the shocks successfully. In this instance, had expensive and massive lighthouses of the usual type been erected, the loss would have been considerable, in view of the severity of this seismic disturbance and the widespread destruction which was wrought. These lights play a very prominent part in the guarding of the southern ocean, the Australian shores being protected by over sixty such beacons, many of which are established in very exposed and isolated positions off the mainland.
While the day is still far distant when expensive graceful towers, carrying immensely powerful lights, will be no longer constructed, the perfection and utility of the unattended light, in one or other of its many forms, are assisting tangibly in the solution of the problem of lighting busy shorelines adequately and inexpensively. Structures costing tens of thousands sterling in future will be restricted to important places, especially in connection with sea-rocks, such as landfalls, or to those some distance from the land, where a fog-signal station must be maintained, unless the example of the Platte Fougère land-controlled station becomes adopted.