PLYM AND TAMAR HUMANE SOCIETY. 87 



ginally promulgated by M. Le Roy, in his researches 

 on Asphyxia (cessation of the pulse.) 



When the arterial blood has once circulated through 

 the body it is unfit to support the vital actions without 

 being submitted to the influence of oxygen gas, one of 

 the constituents of our atmosphere. The blood having 

 circulated once through the body is termed venous, 

 black or carbonised blood and must traverse the circuit 

 of the lungs, where, by the almost immediate contact 

 between it and the oxygen gas contained in the air, it 

 becomes decarbonised, of a florid hue, and again fitted 

 for the purposes of vitality. If, however, breathing be 

 in any way suspended, the blood, cut oiFfrom its necess- 

 ary supply of oxygen, and unable to discharge its carbon, 

 is at length circulated through all parts of the body in 

 the shape of venous or carbonated blood. Such blood 

 acts as a direct poison on the brain and nervous system, 

 depriving them of their volition and sensation, and, in 

 from three to five minutes, the vital spark is utterly 

 extinct. 



Why then it may be asked are our exertions demand- 

 ed if a body has lain for a longer time than this under 

 water? The following is an answer. The sentiment 

 and the sight of death close at hand, or any other im- 

 minent danger, frequently produce a sudden fainting 

 fit. When this suspension of the vital phenomena 

 immediately, or almost immediately, follows immersion, 

 the circulation and respiration are simultaneously stop- 

 ped, black blood does not circulate in the arteries, it 

 does not carry its fatal influence to the vital organs, and 

 the drowned person may sometime afterwards recover 

 his senses as after an ordinary fainting fit. 



M. Le Roy made experiments on animals, in whom 

 syncope is not so easily produced as in man, and found 

 that they could be but seldom restored to life after a 

 submersion of four or five minutes. 



Fodere in his " Medicine Legale," torn. iii. quotes from 

 Plater the case of a female condemned to be drowned 

 for the murder of her own infant, she fainted on being 



