GROWTH OF CELLS AND CRYSTALS. 



55 



conception concerning how this is done. The living matter 

 may increase in size, and I may see it divide and subdivide 

 so as to give rise to other masses like itself. But how it 

 moves, how it grows, how it forms, and how or why it divides, 

 I cannot tell. I know, however, it does not move like any 

 mechanism of which we have any experience, for it moves in 

 any and every direction, and every minute portion exhibits 

 movements of its own accord, not from being pushed or 

 pulled by others. There is no machine that moves of its 

 own accord in any part. The parts of a machine are moved. 

 The living matter does not grow like a crystal, for the 

 stuff of which it is made cannot be detected in the solution 

 around it, nor is the matter deposited particle after particle 

 upon the surface. Neither does it produce chemical com- 

 pounds like the chemist, for, as has been shown, there is 

 nothing like a laboratory, chemicals, apparatus, or chemist 

 there. It may be childish on my part to attribute this 

 movement, this growth, this formation, and this multiplication 

 to some mysterious force or power, or agency of the nature 

 of which I know nothing, and to call it vital power, because 

 it works in living matter only ; but is not anything better 

 than leading people to imagine that you have explained to 

 them the whole matter, when you have really given no 

 explanation at all, and do not understand the thing you 

 have attempted to explain ? The words machine, mechanism, 

 machinery, certainly might be applied to soft, colourless, 

 structureless, growing, moving matter, and watches, and 

 mills, and steam-engines might be called "living things," 

 but it is not easy to see what would be gained. At any 

 rate, the term " machine " ought not to be applied to that 

 which lives, and moves, and grows without our help, and 



