PHYSICAL AND CHEMICAL CHARACTERS. 323 



If this is elementary life, let us ask what is 

 elementary death — i.e.^ the death of the cell. And in 

 this connection let us ask the questions which we have 

 to examine in the case of animals high in organiza- 

 tion, and of man himself What are the characteristics 

 of elementary death ? When the cell dies, is its death 

 preceded by a growing old or senescence? What are 

 the preliminary signs and the acknowledged symptons? 



Changes Produced by Death. — The state of death is 

 only truly realized when the fundamental properties 

 of living matter enumerated above have entirely 

 disappeared. We must follow step by step this dis- 

 appearance in all the anatomical elements of the 

 metazoan. 



Now the properties of the cell are connected with 

 the physical and chemical organization of living 

 matter. For them to disappear entirely, this organ- 

 ization must be destroyed as far as all that is essential 

 in it is concerned. We cannot admit with the 

 vitalists that there is any material difference between 

 the dead and the living, and that only an immaterial 

 principle which has escaped into the air distinguishes 

 the corpse from the animated being. In fact, the 

 external configuration may be almost preserved, and 

 the corpse may bear the aspect and the forms of the 

 preceding state. But this appearance is deceptive. 

 Something in reality has changed. The structure, 

 the chemical composition of the living substance, 

 have undergone essential changes. What are these 

 changes ? 



Physical Changes. — Certain physiologists have 

 endeavoured to determine them. Klemm, a botanist, 

 pointed out in 1895 the physical changes which 

 characterize the death of vegetable cells — loss of 



