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INTRODUCTION. 9 



as to arrest even one of the partial motions of which it is com- 

 posed, the general movement of life must cease. 



Every organized body, independently of the qualities com- 

 mon to its tissue, has a form peculiar to itself, not merely ge- 

 neral and external, but extending to the detail of the structure 

 of eacli of its parts ; and it is upon this form, which determines 

 the particular direction of each of the partial movements that 

 take place in it, that depends the complication of the general 

 movement of its life it constitutes its species and renders it 

 what it is. Each part co-operates in this general movement 

 by a peculiar action, and experiences from it particular effects, 

 so that in every being life is a whole, resulting from the mu- 

 tual action and re-action of all its parts. 



Life, then, in general, pre-supposes organization in gene- 

 ral, and the life proper to each individual being pre-supposes 

 an organization peculiar to that being, just as the movement 

 of a clock pre-supposes the clock ; and accordingly we behold 

 life only in beings that are organized and formed to enjoy it, 

 and all the efforts of philosophy have never been able to dis- 

 cover matter in the act of organization, neither per se, nor by 

 any external cause. In fact, life exercising upon the elements 

 which at every moment form part of the living body, and 

 upon those which it attracts to it, an action contrary to that 

 which, without it, would be produced by the usual chemical 

 affinities, it seems impossible that it can be produced by these 

 affinities, and yet we know of no other power in nature capa- 

 ble of re-uniting previously separated molecules. 



The birth of organized beings is, therefore, the greatest 

 mystery of the organic economy and of all nature : we see 

 them developed, but never being formed ; nay more, all those 

 whose origin we can trace, have at first been attached to a 

 body similar in form to their own, but which was developed 

 before them in a word, to apparent. So long as the offspring 

 has no independent existence, but participates in that of its 

 parent, it is called a germ. 



The place to which the germ is attached, an^. the cause 

 which detaches it* and gives it an independent life, vary ; but 

 Vol. I. B 



