OF ORGANIC COMPOUNDS. 301 



acids, the number of atoms of oxygen being aug- 

 mented by i, by 1, by 2, and by 5. But all the 

 oxygen contained in these compounds, beyond that 

 which belongs to the protoxide, is bound to the 

 manganese by a much morfe feeble affinity ; a red 

 heat causes an evolution of oxygen from the per- 

 oxide, and the manganic and hypermanganic acids 

 cannot be separated from their bases without under- 

 going immediate decomposition. 



There are many facts which prove, that the most 

 simple inorganic compounds are also the most stable, 

 and undergo decomposition with the greatest diffi- 

 culty, whilst those which are of a complex composi- 

 tion yield easily to changes and decompositions. 

 The cause of this evidently^is, that, in proportion to 

 the number of atoms which enter into a compound, 

 the directions in which their attractions act will be 

 more numerous. 



Whatever ideas we may entertain regarding the 

 infinite divisibility of matter in general, the exist- 

 ence of chemical proportions removes every doubt 

 respecting the presence of certain limited groups or 

 masses of matter which we have not the power of 

 dividing. The particles of matter called equivalents 

 in chemistry are not infinitely small, for they possess 

 a weight, and are capable of arranging themselves 

 in the most various ways, and of thus forming 

 innumerable compound atoms. The properties of 

 these compound atoms differ in organic nature, not 

 only according to the form, but also in many instan- 

 ces according to the direction and place, which the 

 simple atoms take in the compound molecules. 



When we compare the composition of organic 

 compounds with inorganic, we are quite amazed at 

 the existence of combinations, in one single molecule 

 of which, ninety or several hundred atoms or equiv- 

 alents are united. Thus, the compound atom of an 

 organic acid of very simple composition, acetic acid, 

 for example, contains twelve equivalents of simple 

 elements ; one atom of kinovic acid contains 33, 1. 

 26 . 



