The French lighthouse service has a magnificent lightship in the _Ruytingen_, which rides in 60 feet of water over a treacherous sandbank outside Dunkirk. It is a steel vessel about 100 feet in length, and displaces in loaded condition about 387 tons. It is held in position by massive umbrella-like anchors, weighing some 2 tons, which, burying themselves in the ground, refuse to drag even under the most fearful tugs and jerks imposed by a gale, while the chains which hold the ship in leash are able to give her a run of approximately 1,000 feet.
The German coast is as dangerous to approach, owing to the shoals and banks, as the eastern shores of England, and one or two magnificent lightships have been built and stationed over the most notorious danger areas, among which may be mentioned the _Norderney_ and _Eider_ vessels. The latter is about 133 feet in length by 24 feet wide, and is fitted with three masts. It throws a fixed white light, which may be seen on all sides from eight to eleven miles away. This boat is fitted with every modern device to increase its warning powers and service, including wireless telegraphy and the submarine bell.
These two latter inventions have improved the serviceability of the lightship to a vast degree, inasmuch as the ocean liners and many freighters are equipped with both these useful handmaids to navigation. The tolling of the bell under water may be heard for several miles, and conveys intimation of the approach to danger in foggy weather, when the siren or other fog-signal is somewhat precarious.
The _Norderney_ lightship is probably one of the finest craft in operation upon the seven seas. Before it was designed the German engineers carried out a thorough inspection of all the most modern lightships in service in Europe, and from the results of their investigations contrived this magnificent aid to navigation. The vessel is about 150 feet in length, and is built of steel. The light is shown from a lantern fitted with a third-order pendular lens carried at the top of a hollow steel mast. The illuminant used is Pintsch’s oil-gas, with incandescent mantle, the fuel being stored in reservoirs stowed in the hold of the ship; fresh supplies are brought out by the tender at periodical intervals. Weight-driven clockwork mechanism is employed to revolve the lantern. The light is one of the most powerful in European waters, 50,000 candle-power being emitted with an incandescent gas mantle having a diameter of 30 millimetres (1¼ inches).