THE MECHANISM OF LIFE 219 



the same. The artificial cell, however, would 

 possess the properties, though merely physical ones, 

 which would entitle us to attribute some form of 

 life to it. Once more, then, we see how near we 

 may approximate to the natural phenomena and 

 yet how far we remain from the actual thing ; 

 perhaps, indeed, as far as ever. Still, it is some- 

 thing to approximate even if we do not reach 

 the end. " To travel hopefully is better than 

 to arrive, and the true success is to labour." 

 Those artificial cells may never, and we think 

 will never, bring us to the goal ; but in thus 

 travelling, in thought at least, with the progress of 

 these ideas we may arrive at a clearer comprehen- 

 sion as to what the nature of that goal shall be. 



The element which we suppose to constitute 

 the material of the ultimate nucleus is thus the 

 hereditary substance. It is generally held that 

 protoplasm does not contain the necessary here- 

 ditary material. Eeference has already been made 

 to the experiments of Boveri. Amongst others 

 who would agree with this view are Weismann 

 and Hertwig, who postulated such an hereditary 

 substance. The point that it has been our object 

 to explain is that such substance, if it possessed 

 properties akin to those of the unstable elements, 

 would also account for the formation of the 

 properties of the cell. No doubt there would be 

 a great variety of such substances, particularly on 

 account of their unstable nature. We have seen 

 that other elements than radium can produce 



