208 THE PHENOMENA OF MOTION 



chemical force of another chemical compound, and 

 that without its manifestation being enfeebled or 

 arrested by resistance. Thus the equilibrium in the 

 attraction between the elements of cane-sugar is 

 destroyed by contact 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 influence, arrange themselves with 

 those of water in a new form, while the sulphuric 

 acid, which has served to produce these transforma- 

 tions, 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-called mechanical forces, we have recognized in 

 the chemical forces causes of motion and of change 

 in form and structure, without any observable ex- 

 haustion of the force by which these phenomena 

 are produced ; but the origin of the continued 

 manifestation of activity remains still the same ; it 

 is the absence of an opposite force (a resistance) 

 capable of neutralizing it or bringing it into the 

 state of equilibrium. 



As the manifestations of chemical forces (the 

 momentum of force in a chemical compound) seem 

 to depend on a certain order in which the elemen- 

 tary particles are united together, so experience 

 tells us, that the vital phenomena are inseparable 



