ON DEATH. 15 



On the Influence of the Death of the Lungs upon that 

 of the Organs generally. 



Q. How do you ascertain the progress of asphyxia in 

 animals? 



#. Tie the trachea high up; make an opening below 

 the ligature, introduce a tube with a cock to it. By this 

 means you can admit air as you please to the lungs. Adapt- 

 a small tube and cock to the crural artery, and by this you 

 ascertain the state of the blood in the progress of the 

 asphyxia. 



Q. If the cock of the pipe be shut immediately after 

 inspiration, what changes are made in the blood? ^ 



/2. In thirty seconds the blood begins to darken; in a 

 minute its colour is deepened; in two minutes it is black 

 blood. 



Q. What is the effect of stopping the cock after a strong 

 expiration? 



/?. The blood becomes sooner black. 



Q. What takes place when you pump the air from the 

 lungs with a syringe? 



#. The blood blackens immediately; the crural artery 

 throws a black stream, as soon as the red blood which it 

 contained can be emptied. 



Q. And what if the air cells are completely filled be- 

 fore the cock is stopped ? 



#. The blood is slower in becoming black. 

 Q. After asphyxia has been established for some mi- 

 nutes, if the stop be opened, what takes place? 



#. A strong expiration first takes place; then several 

 deep rapid respirations, and an instantaneous, not gradual 

 restoration of the blood to a red colour. These changes 



