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

FIRST AID TO THE DIVER IN CASE OF ACCIDENT. Possible accidents to deep-sea divers may be considered under four heads: — (t) Caisson disease. (2) Asphyxia, or CO2 poisoning. (3) Drowning. (4) Hemorrhage. We have already seen that the cause of caisson disease is the formation of air bubbles in the blood of tissues, owing to the too sudden decompression of the diver. Symptoms.—Symptoms vary with the severity of the case. The first class of cases is that associated with symptoms of asphyxiation. These come on about four or five minutes after the diver has come up from a fairly long stay in deep water. They commence with a feeling of indefinite distress—-pain in the pit of the stomach—diffi- culty of breathing—the patient becomes livid and rapidly unconscious—the heart-beats become weaker and then stop. Such a case as this is alarming, but fortunately it is rare. Owing to the cause of this condition nothing that can be done at atmospheric pres- sure is of much service, and the only chance of recovery is quickly to recompress the sufferer. If the weights have been removed they must be rapidly replaced, the glass of the helmet screwed up, the exhaust valve freely opened and the diver lowered slowly, with the pumps heaving, for 10 or 15 fathoms. Even if the diver is quite unconscious this procedure should be followed, as it affords the only chance of his life being saved. A second diver should be sent down as quickly as possible to observe the condition of the sufferer. If the latter has recovered consciousness, he should be allowed to stay down for some time at the depth to which he has been lowered, and then very gradually, by stages, brought to the surface again. A second class of cases is that where paralytic symptoms come on from ten minutes to half an hour after the diver has returned to the surface. In these cases there often is, as the first symptom, pain in the stomach, followed by pains of a “pins and needles ” type in the arms and legs, inability to pass water, and then loss of power in the arms and legs. Recompression is undoubtedly the best treatment in these cases. If the ship is not provided with a special steel chamber in which the diver can be recom- pressed (see page 18), he should be lowered down again into 10 or 15 fathoms of water, allowed to stay at that depth for some time, and then very cautiously brought to the surface. In these cases the inhalation of oxygen might be substituted for the recom- pression if that gas is at hand. The third class of cases is that in which severe pains develop in or about the joints, the “bends or screws” of the caisson worker. These pains develop at a later period, say from half to two hours after coming to the surface. The pains will pass off in time, but can be at once relieved by the diver descending into the water again. O'