46 THE GENERAL CHARACTERS OF CELLS, BY S. STRICKER. 



not enable us to arrive at any positive decision, unless their 

 action is sufficiently slight to excite movements, but not to 

 effect complete destruction. This is indeed true of all other 

 agents, for they can only furnish us with information in regard 

 to the life of the cell when they produce changes which our 

 experience teaches us are ascribable to life ; on the other hand, 

 it is often easy to determine that a particular cell is dead. The 

 greater number of chemical reactions refer to the phenomena 

 exhibited by dead cells. The forms which cells killed by 

 chemical agents present are so various that they cannot be 

 enumerated, but the most important have been treated of in 

 the first chapter. 



If the cells have been killed by powerful electric currents, 

 by a high temperature, or by mechanical violence, the deter- 

 mination of their condition, after what has already been said 

 upon the effects of these agents, can no longer be doubtful. 

 But if no remarkable alterations of form (flattening, tearing, 

 bursting), no remarkable physical alterations (cloudiness, coagu- 

 lation), and lastly, no definite change resulting from the action 

 of the fluid in which they have been preserved, furnish indica- 

 tions of the death of the cells, no scientific value can be attri- 

 buted to any statement made respecting it. 



