LIVING MATTER 35 



one half of the original cell. Some such process of 

 multiplication takes place in all living things, but 

 this important matter is one which will require 

 fuller treatment in a succeeding chapter. 



Last scene of all which ends this strange event- Death 

 ful history, the amoeba may die. Weismann 

 teaches that the unicellular organism is potentially 

 immortal, and indeed there seems to be no reason 

 why an amoeba should not go on living for an 

 indefinite period, unless we regard the time when a 

 given amoeba divides into two new forms as being 

 really a period or moment of dissolution and re- 

 creation. But, at any rate, it is quite clear that 

 we can kill an amoeba by a strong current of 

 electricity, by exposing it to a temperature higher 

 than it can bear, or by mixing certain chemicals 

 with the water in which it lives. Under any one 

 of these circumstances the amoeba dies, that is the 

 living substance of which it consisted becomes not- 

 living and the oxygen and other chemical sub- 

 stances which had up to this moment been its 

 slaves now become its masters and destroy it. 

 " This change is associated with alterations in the 

 mechanical and optical properties of the protoplasm, 

 which loses its viscidity and becomes opaque, 

 having undergone a process of ^-solution ; for the 

 water it contained is now held only mechanically in 

 the interstices of a network, or in cavities of a 



