THE EDDYSTONE LIGHT.

Timaru Herald, Volume CXXXIII, Issue 18763, 30 December 1930, Page 9

THE EDDYSTONE LIGHT.

STONE FORTRESS OUT AT SEA. Fifty years ago the great granite squares which were to form the base of the Eddystone Lighthouse were being assembled at Plymouth. For centuries British engineers had battled with the problems presented by the wicked coastline of South-western England. Successive edifices had been swept away by the wind and waves as though they had been built of straw. No other ocean highway in the world was hedged by a shore which called for such a number of warning lights. The first Eddystone, built of wood, was erected in the year 1700. Winstanley. the engineer who designed -it, was himself killed when it was carried away three years later. In 1709 a bigger and stronger wooden structure was put up by Rudyard. It caught fire, and was destroyed 46 years later. Smeaton built the third, taking as his model the trunk of an oak tree. He used granite and Portland stone, and for over ten years his creation defied the gale of the Cornish coast. In 1878 work was commenced on the present building, of which Sir James Douglas was the designer, and it was completed four years later. Work on the foundation could only be carried out at low water. Great steel rods were driven deep into the rocks. On to these were skewered the massive blocks of stone which had been prepared ashore. In order to make them lock tightly together these blocks were dove-tailed.

A long study of the problem of coast . .osion had proved that the laying of rectangular stones upon each other, in the ordinary way, with the use of jointing material, had not given the maximum of stability. The receding water had sucked the motor from between the stones, leaving a space into which the oncoming waves had forced air. A sort of pneumatic action was thus set up, with the result that as the waves rolled back the sudden escape of imprisoned and compressed air actually moved the masonry. The stone base on which the Eddystone tower rests rears itself a full 25ft above the normal water level. Into its floor are sunk two tanks each capable of storing 5000 gallons of fresh water. The entrance to the tower is guarded by two doors, one of gunmetal, which weighs a ton, and an inner one of solid teak. The walls of the tower, which is built to stand a wind pressure of 777001 b to the square foot, are Bft thick, and the tower itself consists of 2000 blocks of granite, each weighing two tons.

Although permanency was the main thing aimed at, no fault can be found with Eddystone lighthouse from an architectural point of view. Even its contour is rhythmic and imposing. As far as the navigator is concerned, however (and he is the person chiefly interested), the light is the vital thing. Since the age of Ptolemy 11., who caused to be built on the Island of Pharos, off Alexandria, the first of all the real lighthouses, the matter which has chiefly engaged the attention of scientists has been the intensification and mobility of the light. The very earliest type of light used was an open wood fire, burning upon a coastal eminence. The brazier gave place in time to the tallow candle. Gas eventually superseded the candle, just as gas is now being ousted by electricity. During the last 100 years most progress has been made in connection with the diffusion of the available light, and the experiments made by engineers have had as their main object the ideal arrangement of reflectors and the greatest possible range of the beam.

Trinity House, is, of course, the authority responsible for the lights which are dotted along the shores of Britain. Venerable as Trinity House may be, it is alive to-day to its onerous responsibilities as ever it was. Now that the bulk production of electricity is bringing down the price of light, the “House” is steadily engaged in the electrification of all its light-ships and light-houses. Eddystone. partly because of its remoteness and consequent inaccessibility, has not yet had electricity installed, but it is “on the list.” St. Catherine’s point, which warns ships of the Atherfield Ledge, off the Isle of Wight, walls electrified 30 years ago. Owing to the curvature of the earth’s surface a ground light cannot be picked up at distance much greater than 18 miles, but what is called the “doom” of St. Catherine’s light can on a clear night be seen quite plainly in the Channel Islands 70 miles away. Year by year the number of disasters at sea becomes steadily less, and it is to the fact that Trinity House never wearies in its task of safeguarding the sailor that this satisfactory state of affairs is largely due. Much as Britain owes to her indomitable mariners, they in their turn are loud in proclaiming their gratitude to the authorities ashore, whose principal job it is to give them safety on their coastwise voyages.