242 Mr. Faraday on holding the Breath 



nary circumstances. It is as follows: — If a person inspire 

 deeply, he will be able immediately after to hold breath for a 

 time, varying with his health, and also very much with the state 

 of exertion or repose in which he may be at the instant. A 

 man, during an active walk, may not be able to cease from 

 breathing for more than half a minute, who, after a period of 

 rest on a chair or in bed, may refrain for a minute or a minute 

 and a half, or even two minutes. But if that person will pre- 

 pare himself by breathing in a manner deep, hard and quick, 

 (as he would naturally do after running,) and, ceasing that ope- 

 ration with his lungs full of air, then hold his breath as long 

 as he is able, he will find that the time during which he can 

 remain without breathing will be double, or even more than 

 double the former, other circumstances being the same. I 

 hope that I have here stated Sir Graves C. Haughton's com- 

 munication to me correctly; at all events whilst confirming 

 his observation by personal experience, I found the results to 

 be as above. 



Whilst thus preparing myself, I always find that certain 

 feelings come on resembling in a slight degree those produced 

 by breathing a small dose of nitrous oxide; slight dizziness and 

 confusion in the head are at last produced; but on ceasing to 

 breathe, the feeling gradually goes off, no inconvenience results 

 from it either at the time or afterwards, and I can hold my 

 breath comfortably for a minute and a quarter, or a minute 

 and a half, walking briskly about in the mean time. 



Now this effect may be rendered exceedingly valuable. 

 There are many occasions on which a person who can hold 

 breath for a minute or two minutes, might save the life of 

 another. If, in a brewer's fermenting vat, or an opened cess- 

 pool, one man sinks senseless and helpless, from breathing the 

 unsuspected noxious atmosphere within, another man of cool 

 mind would by means of this mode of preparation, which re- 

 quires nothing but what is always at hand, have abundant 

 time, in most cases, to descend by the ladder or the bucket, 

 and rescue the sufferer without any risk on his own part. If 

 a chamber were on fire, the difference in the help which could 

 be given to any one within it by a person thus prepared, and 

 another who goes in, perhaps, with lungs partially exhausted, 

 and who, if he inhale any portion of the empyreumatic va- 

 pours of the atmosphere, is stimulated to inspire more rapidly, 

 and is therefore urged to instant retreat into fresh air, is so 

 great, that no one who has noticed what can be done in a mi- 

 nute or in two minutes of time can doubt the value of the 

 preparation under such circumstances, even though from want 

 of practice and from hurry and alarm it may be very imper- 



