UNDER SEA WITH HELMET AND CAMERA 



will need more air on account of his physical exertion. The proper way 

 to supply air would be always to pump more than required, but this 

 puts a strain on the man at the pump because he has no way of knowing 

 how much more than enough he is delivering, and desiring to err on the 

 safe side, is likely to over exert himself. 



Some of us will become so enthusiastic over this diving business that 

 if we have the means, we will go into it more elaborately and will not be 

 bothered with this matter of pumping air by hand. A motor driven pump 

 will be used, and it will furnish an excess of air at the greatest depth. But 

 I must recommend earnestly that such a pump not be used unless it is of 

 the very best make and most carefully installed. Everything else should 

 be placed a step forward in the way of facilities. If we have a motor 

 driven pump we want a better boat to keep it on, and a thoroughly re- 

 liable source of power. One improvement will necessitate another, and 

 our whole outfit will be quite different from that which Eddie, Carol 

 and John used. Therefore, unless we are going to make a very definite 

 change in equipment we had better stick to the old "armstrong" pump. 



I have mentioned the matter of forgetfulness which comes over a 

 diver. This is a real danger to be guarded against by the professional 

 deep-sea divers. It is held to be caused by inhaling too much oxygen, 

 and getting a sort of "jag." Divers at great depths have not answered 

 their calls, and someone has had to go down to them. They have been 

 found wandering aimlessly and oblivious to signals. 



Excess of oxygen can hardly be the cause of the forgetfulness that I 

 have experienced. It may come from insufficient oxygen, which has a 

 similar effect upon aviators when they rise to great altitudes. The mind 

 becomes sluggish, but immediately returns to its normal process when 

 the flier uses his flask of oxygen. 



Another cause of forgetfulness may be the unreahty of the experience 

 under water. The diver is perforce slow in his motions and his vision is 



