OF ORGANIC COMPOUNDS. 235 



the power of forming numerous combinations 

 amongst themselves by their mutual attractions. 



Now, when we examine what changes sugar 

 undergoes when brought into contact with other 

 bodies which exercise a marked influence upon it, 

 we find, that these changes are not confined to any 

 narrow limits, like those of inorganic bodies, but 

 are in fact unlimited. 



The elements of sugar yield to every attraction, 

 and to each in a peculiar manner. In inorganic 

 compounds, an acid acts upon a particular consti- 

 tuent of the body, which it decomposes, by virtue of 

 its affinity for that constituent, and never resigns 

 its proper chemical character, in whatever form it 

 may be applied. But when it acts upon sugar, and 

 induces great changes in it, it does this, not by its 

 superior affinity for a base existing in the sugar, 

 but by disturbing the equilibrium in the mutual 

 attraction of the elements of the sugar amongst 

 themselves. Muriatic and sulphuric acids, which 

 differ so much from one another both in characters 

 and composition, act in the same manner upon 

 sugar. But the action of both varies according to 

 the state in which they are ; thus they act in one 

 way when dilute, in another when concentrated, and 

 even differences in their temperature cause a change 

 in their action. Thus sulphuric acid of a moderate 

 degree of concentration converts sugar into a black 

 carbonaceous matter, forming at the same time 

 acetic and formic acids. But when the acid is more 



