THE PHYSIOLOGY OP DEATH. 305 



the end of the eighteenth century did death in action be- 

 come the subject of investigation by Bichat. 



Bichat is the greatest of the physiological historians of 

 death. The famous work he has left on this subject, his 

 " Physiological Researches upon Life and Death," is as 

 noteworthy for the grandeur of its general ideas, and its 

 beauty of style, as for its precision of facts and nicety of 

 experiment. To this day it remains the richest mine of re- 

 corded truths as to the physiology of death. Having de- 

 termined the fact that life is seriously endangered only by 

 alterations in one of the three essential organs, the brain, 

 the heart, and the lungs, a group forming the vital tripod, 

 Bichat examines how the death of one of these three or- 

 gans assures that of the others, and in succession the 

 gradual stoppage of all the functions. In our day, the ad- 

 vance of experimental physiology in the path so success- 

 fully traversed by Bichat, has brought to light in their mi- 

 nutest details the various mechanical processes of death, 

 and, what is of far greater consequence, has disclosed an 

 entire order of activities heretofore only suspected to be at 

 work in the corpse. The theory of death has been built 

 up by slow degrees along with that of life, and several 

 practical questions that had remained in a state of uncer- 

 tainty, such as that of the signs of real death, have re- 

 ceived the most decisive answer in the course of these re. 

 searches. 



I. 



Bichat pointed out that the complete life of animals is 

 made up of two orders of phenomena, those of circulation 

 and nutrition, and those that fix the relations of the living 

 being with its environment. He distinguishes organic life 

 from animal life, properly so called. Vegetables have only 

 the former; animals possess both, intimately blended. 

 Now, on the occurrence of death, these two sorts of life do 



not disappear at one and the same moment. It is the ani- 

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