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

reasonable distance of the surface. After the first long stage the subsequent stages must be taken with frequent pauses, in order to let the excess of nitrogen pass off through the lungs, the longest pause being made a few feet below the surface. It need hardly be stated that the time of the pauses must be signalled from the sur- face, as, very naturally, the diver has but very little notion of time. Gymnastic Exercise when coming up. While the diver is coming up the shot rope he must at each stop do as much gymnastic exercise as possible, especially using those muscles which were in use on the bottom. This will increase the circulation so that the blood is more rapidly desaturated. It is also a good plan to stop all but one pump after the first stage, as a little excess of CO2 in the helmet will increase the respiration and circulation, and thus help in the removal of nitrogen. Copyright. Photo No. 8. Recompression Chamber, as referred to on page 7. 18