46 ON DEATH. 



are more or less complete according to the quantity of 

 air admitted. 



Q. From the rapidity with which the blood is reddened, 

 what do you suppose to be the course of the colouring 

 principle? 



A. There can be little doubt that the colouring matter 

 passes the membranes of the air cells to the blood, and not 

 through the absorbents. 



Q. When asphyxia is removed by the introduction of 

 air, how is the heart affected ? 



fl. Red blood is sent to the left heart, it penetrates the 

 coronary arteries, and reanimates the forces of the heart, 

 which were exhausted by the black blood. 



Q. If the heart's action is once entirely checked, can it 

 be restored by the injection of air into the lungs? 



ifl. It cannot. The heart having ceased to beat, the 

 coronary arteries no longer nourish the vital forces of the 

 heart with blood. A temporary syncope may be removed. 



Q. What are the symptoms in asphyxia from hydrogen 

 and carbonic acid gas? 



/?. After a hurried, agitated, embarrassed respiration 

 for a few minutes, the blood becomes black. 



Q. Why is the blood longer in blackening when these 

 gases are respired? 



#. The expelled and reabsorbed air in this process, af- 

 fords all its vivifying principles to the blood. But when 

 the tube and cock are simply shut, there is not this agita- 

 tion of the respirable air remaining in the lungs. 



Q. If oxygen be respired, what occurs? 



#. The blood is much longer in losing its red colour.' 



Q. How do you prove that black blood is circulated in 

 the organs in asphyxia? 



