PROPERTIES OF LIVING MATTER. 



105 



regards the dependence of the properties of these two 

 totally dissimilar substances upon the properties of their 

 constituent elements. It might be objected, that of water 

 there is but one kind, while of protoplasm it must be 

 admitted that there are kinds innumerable, but a hostile 

 critic has sagaciously remarked that there are at least two 

 kinds of water, dirty water and clean water ! Again, the 

 constituent elements of the same particle of water may be 

 separated and recombined as many times as we please ; but 

 the elements of protoplasm once separated from one another 

 can never be combined again by us to form any kind of 

 protoplasm, or anything at all like protoplasm. The argu- 

 ment advanced against vitality^ as far as it rests upon the 

 non-existence of aquosity, is perfectly childish, and it is 

 astonishing that any writer who gave his readers credit for 

 possessing very moderate intelligence should have adduced 

 it at all. 



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. It is quite true that no one can demonstrate by 

 physical investigation any difference between the " proto- 

 plasm" of the embryo, say, of a worm, of a dog, and of a 

 man, and I have myself dwelt upon this, but it by no means 

 follows that the "properties " of protoplasm to form worm, 

 sheep, bird, man, &c., as the case may be, are due to the 

 arrangement and nature of the component molecules, and 

 of which neither Mr. Huxley, nor any one else, knows any- 

 thing whatever. To attribute the different results of the 

 development of the several protoplasms to differences in 

 physical and chemical constitution is not warranted, because 



