VITAL PROPERTIES. 29 



be separated and recombined again and again as many 

 times as we please; but the elements of protoplasm once 

 separated from one another, can never be combined again 

 to form any kind of protoplasm. But further, every kind of 

 protoplasm differs from every other kind most remarkably 

 in the results of its living, one producing man, another dog, 

 a third butterfly, a fourth amoeba, and so on. Now, what 

 can be more absurd than to suggest that the properties of 

 man, dog, butterfly, and amoeba are due not to vitality, but 

 to the constituent elements, or to the properties of the 

 molecules of their tissues ? Do the properties of the 

 elements of dog differ sufficiently from those of the ele- 

 ments of man, to account for the differences between 

 dog and man. Have we not rather reason to infer an 

 approximation towards identity of composition in the living 

 matter, with marvellous difference in the results of the vital 

 actions ? How, then, can the differences be due to the 

 ordinary properties of the elements ? Wonderful properties 

 have indeed to be discovered in connection with elements 

 before we can refer the differences in property of living 

 beings compounded of them to the properties of the ele- 

 ments themselves. The argument advanced against vitality, 

 as far as it rests upon the non-existence of aquosity, is 

 utterly worthless, and it is astonishing that any writer who 

 gave his readers credit for moderate intelligence should 

 have adduced it at all. 



To sum up in few words. The term protoplasm has 

 been applied to the viscid nitrogenous substance within the 

 primordial utricle of the vegetable cell and to the threads 

 and filaments formed in this matter; to the primordial 



