A DIVER’S GREATEST DANGER.
The greatest enemy of the diver is paralysis, and this, strangely enough, is not caused by sending him into the sea, but in carelessly taking him out of it. In bringing a diver to the surface from any great depth, as much as half an hour is spent in what is known as “staging” him. He is brought up to a certain depth from the surface and there held, while he fights vigorously with arms and legs to quicken the circulation temporarily, and so to assist in sweeping the excess of nitrogen out of the tissues of the body. This excess of nitrogen, forced into the blood under pressure of air and water, is the cause of diver’s paralysis. At various depths before reaching the surface, the good diver, who understands what causes paralysis, will “stage” and prepare himself to leave the water. Once on the deck of the lugger, he will rest and recover himself for another descent, and so throughout the day.