178 SECRETS OF ANIMAL LIFE 



for months in conditions where no respiratory 

 exchange with the outer world was possible. 

 Becquerel showed that seeds deprived by an air- 

 pump of their internal atmosphere and kept for 

 a year under mercury, or in nitrogen or carbon 

 dioxide, or in a nearly complete vacuum, still retain 

 their power of germinating. What is this life 

 that sulks and hides itself, but will not die? Life 

 is a kind of activity, a series of correlated reactions 

 among the members of a well-constituted chemical 

 firm, and taking place in what is called a colloidal 

 substratum which is to the essential activity of the 

 protoplasm as the bed of a river to its flow; but the 

 activity can only occur in an appropriate environ- 

 ment of air and moisture and the like. So the 

 question is, whether the latent condition implies 

 a total suspension of vital activities, or "an ex- 

 tremely sluggish, intracellular, anaerobic life?" 

 There is a blockade, but does the firm entirely 

 suspend operations, or does it keep going in a small 

 way, which we cannot detect ? 



The great French physiologist Claude Bernard, 

 to whom we owe the term " latent life," maintained, 

 in his classic work on " The phenomena of life com- 

 mon to plants and animals," that life is a rela- 

 tion between organism and environment, and that 

 in dry seeds and desiccated animals it is only poten- 

 tial. "It exists ready to manifest itself if appro- 

 priate external conditions are available, but there 

 is not the slightest manifestation of it if these con- 

 ditions are lacking." Living is not attenuated 



