IN THE ANIMAL ORGANISM. 197 



impeded by other forces, a blow, or mechanical fric- 

 tion, or the contact of a substance, the particles of 

 which are in a state of motion (decomposition, trans- 

 formation), or any external cause, whose activity is 

 added to the stronger attraction of the elementary par- 

 ticles in another direction, may suffice to give the pre- 

 ponderance to this stronger attraction, to overcome the 

 vis inertia?, to alter the form and structure of the com- 

 pound, which are the result of foreign causes, and to 

 produce the resolution of the compound into one or 

 more new compounds with altered properties. 



Transformations, or, as they may be called, phe- 

 nomena of motion, in compounds of this class, may 

 be effected by means of the free and available chemi- 

 cal force of another chemical compound, and that with- 

 out its manifestation being enfeebled or arrested by 

 resistance. Thus the equilibrium in the attraction be- 

 tween the elements of cane-sugar*is destroyed by con- 

 tact with a very small quantity of sulphuric acid, and 

 it is converted into grape-sugar. In the same way 

 we see the elements of starch, under the same influ- 

 ence, arrange themselves with those of water in a new 

 form, while the sulphuric acid, which has served to 

 produce these transformations, loses nothing of its 

 chemical character. In regard to other substances on 

 which it acts, it remains as active as before, exactly 

 as if it had exerted no sort of influence on the cane- 

 sugar or starch. 



In contradistinction to the manifestations of the so- 

 17* 



