Submarine Appliances And Their Uses
Deep Sea Diving, &c., &c.

The best course, therefore, when working in such a position is to keep the valve wide open. No air will escape from it while the head is down. As soon as the diver feels that the accumulation of air along his back is beginning to lift him, he must raise his head, kneeling up if necessary, so that the valve becomes higher than the back, and all the air will then escape with a rush. This will enable him to get his head down again, and proceed with the work for another short spell, after which the process must be repeated. Searching for Lost Articles.—The diver should explore the whole of the ground within the sweep of his distance-line as thoroughly and expeditiously as possible. To do this he may go out to the end of the distance - line, and, keeping it taut, sweep round in a circle. When he comes back to the place he started from (which must be judged by some object on the ground, his own footprints, or the direction of the tide, etc.), he fleets in a short distance along the distance-line, and makes a fresh circle in the opposite direction, thus avoiding the twisting of his pipe and breast rope round the shot rope. It is generally more advantageous to crawl on the bottom when searching, though in exceptionally clear water a better field of vision may be obtained by walking. The diver should not fleet in too much, but should let each new circle just overlap the last. When a diver has explored the whole of the ground in this way without finding the object sought for, he may be certain that it is not within reach of the distance-line. He should therefore come up and ask that the shot, or the boat, may be shifted so that a new area may be searched. Crawling about the bottom at random, in any direction, on the chance of knock- ing up against the object is not the proper method of searching ; however long the pro- cess is continued there can be no certainty that the object of the search is not lying within the area that has been so perfunctorily examined. The method indicated above should always be followed, and will save time in the end. On finding the thing sought for, the diver should immediately fasten his dis- tance-line to it, after which he may signal for a rope and have it hauled up, or go up and make his report as circumstances require. The object can always be found again by the distance-line. Diver Feeling III while under Water.—If the diver feels “ bad” while under water, the cause may be an insufficient supply of air. The usual symptoms in such a case are a sensation of distress, with deep breathing or panting, and a dazed feeling as if consciousness were going. Under these circumstances, the worst thing a man can do is to attempt to go up to the surface, since any exertion when breathing vitiated air greatly increases its bad effects. CM