FRENCH SUBMARINES.

New Zealand Herald, Volume LV, Issue 16895, 6 July 1918, Page 2 (Supplement)

FRENCH SUBMARINES.

NEW DESIGNS.

USE OF THE GYROSCOPIC COMPASS

A SPECIAL correspondent of the Morning Post recently visited the French fleet at a certain port. He writes:

It might have been accident or design, but immediately after visiting the dirigibles and the captive balloons, two of the most active enemies of the submarines, we were invited to see the various types of the French submarine. The French submarine, like tho British, has found it difficult to justify the vast potentialities that lay before it, and in submarine warfare tho Germans have had 90 per cent, of the opportunities, while the allied submarines have had to content themselves with a bare 10 per cent, of chances. The war had scarcely started when every enemy craft other than warships wore driven from tho seas, and the allied submarines have had thai hard task of concentrating their efforts against vessels who were trained at all points to meet their attacks. Had thia situation been reversed and Germany boon master of the seas the position would bo far from what it is now, as Viscount Jcllicoe has explained. Tho German High Seas Fleet knows very well and fears tho reception that awaits it from British submarines on each occasion that it vontures to put out from its minefields.

The French submarines, however, aro all war worn and war hardened. Wo sawmany of them lying in tho port, and it was an impressivo sight to watch them as they lay tied up to tho jetty waiting for action. What struck ouo was that these boats that wore lying in harbour were merely one relay of vessels that had come in from the. sea, and were resting a day or two in port, and preparing to forget for a time the discomforts incidental to life on the submarine, A Box oi Complex Machinery. Like all submarines, tho French submarine is full of complex machinery, a contraption of Diesel engines, accumulators, electric motors, compasses, pumps, and delicate apparatus tf all sorts, and it is one of tho glories of France to have realised the importance of the submarine in war. There is scarcely room for a fully-grown man to stand upright in any of iho older hypes, and men and officers suffer uncomplainingly, not the horoic sort of suffering 1 where the risk amply compensates tho discomfort, but the suffering from cramp, from seasickness, from close" proximity, from the fact ■ that tho engineer is unable to get at his engine in a workmanlike manner, from the feeling that is hardest of all to fight against, that 99 times out of 100 the interests of their country would not suffer if their work were left undone, and yet, all the time, the work goes on, and it goes on uncomplainingly. Naturally, it is impossible to write of much that is new in the submarine work, but from conversations with several submarine officers, I learnt that on broad lines the greatest discovery in connection with the submarine has been the adaptation of the Sperry compass. It needs no knowledge of the theory of tho compass to realise that in an iron vessel whero one quarter of the length is devoted to Diesel engines, one fifth to electric motors, and most of the rest of the boat to moving bits of metal, that no possible compensation of the ordinary compass can make it reliable. The Sperry compass was known in battleships before the war, but it is since the war that it .has been adapted to the submarine. It is a weird invention, and it requires a knowledge of the higher mathematics really to understand the theory on which it is based. What can be said of it is that it dopenda fundamentally on the gyroscope, No matter what happens, when it has been running for a short lime, the compass points persistently to tho north quite independently of tho magnetic influences of the vessel There is nothing, I was assured, that has done more to make the submarine a weapon of precision than the adaptation to it of this compass, which makes it possible for the submarine commander to obtain absolutely accurate bearings. Tobacco Smoke Chemically Removed.

Not all submarines are uncomfortable craft, and we had an opportunity of visiting one of the latest of the French types, and in this the commander has what may be fairly described as a corafortablo cabin. At any rate, he can stand upright in it. The accumulators are all placed closo to the keel, and the engineers are able, if with difficulty, to make a passage not only in front but behind their engines. The ventilation of the vessel has been perfected to such a degree that it is possible to remain below for a long period of time, and even to smoke. The officer of the port told mo that on one occasion when he visited the submarine it had been kept under water for a long time for experimental purposes. Officers and men had been allowed to smoke. Oxygen was supplied to the vessel by the usual methods (chemically), and the various gases of respiration and tobacco smoke were all thoroughly absorbed by the chemicals used. He found to his surprise when the vessel emerged that it was impossible to tell that anyone had been smoking in her.