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is not primitive, for the predisposition which leads to the change 

 is preceded and produced by one of the spirit. 



10. The spirit has also the additional indirect relation with 

 the chemical through the mechanical department. This relation is 

 exemplified in all cases in which the natural relation between the 

 spirit and the mechanicals is disturbed; and the effects of which are 

 afterwards communicated to the chymical connections. In this way 

 it is exemplified in wounds, and in all mechanical injuries in conse- 

 quence of which the spirit is affected, and then modifies the struc- 

 tures or the secretions, 



11. The relation between the spiritual and mechanical, as be- 

 fore remarked, cannot be distinguished from that between the 

 former and the chymical department, in processes of growth; 

 because the particles which compose the structures are constituted 

 by chymical properties. 



12. But this relation, namely, that between the spirit and the 

 mechanicals, may be considered according to the folio wing division: 

 1st, the spirit with the material particles, as a power by which their 

 place is assigned; 2nd, as a power by which they are moved; 3rd, 

 as the spirit is influenced by their place; 4th, as the spirit is influ- 

 enced by their motion. These four divisions include the modes by 

 which the properties of matter are acted upon and operate in the 

 constitution of animal bodies. 



13. 1. The first has been already sufficiently remarked upon : 

 the chymical constitution of the particles interfere to prevent a 

 precise distinction. 



14. 2. The power which the spirit possesses of giving motion 

 to the material parts is copiously exemplified. This power is exerted 

 in the motion of the solids belonging both to the organic and the 

 animal departments, and in the motions of the fluids. The relation 

 of the spirit in producing motion is with the structures, by which 

 latter, motion is communicated to the fluids; in some instances 

 the affinity of certain fluids with the spirit may be a cause of their 

 motion, but to what extent is not ascertained. The properties of 

 the spirit have their seat in the minutest spheres of the textures; 

 their alliance is not simply with particles possessing the common 

 properties of matter, but those precisely formed, as we find them, 

 by chymical constituents. It is therefore probable that the relation 

 of the spirit with the textures, by which the motions of the latter 

 are occasioned, is not directly with the common properties of mat- 

 ter, but through the medium of peculiar constituents belonging to 

 the matter, and which, as they are found united with chymical 

 materials, can scarcely be separated from this class. 



15. We find that mechanical agents, which produce sensible 

 effects upon the principle of life, belonging to either system, produce 

 these effects through the medium of the established textures. This 

 relation between organic and foreign matter is one which requires 

 contact; and by contact the influence of foreign matter is comprised 

 in the modifications of pressure, which pressure, so far as the 



