27u CHEMICAL TRANSFORMATIONS. 



manganese by absorption of oxygen is converted into the sesqui- 

 oxide, the peroxide, manganic and hypermanganic acids, the 

 number of atoms of oxygen being augmented by $, by 2, by 3, 

 and by 3£. But all the oxygen contained in these compounds, 

 beyond that which belongs to the protoxide, is bound to the man- 

 ganese by a much more feeble affinity ; a red heat causes an 

 evolution of oxygen from the peroxide, and the manganic and 

 hypermanganic acids cannot be separated from their bases with- 

 out undergoing immediate decomposition. 



There are many facts which prove, that the most simple inor- 

 ganic compounds are also the most stable, and undergo decom- 

 position with the greatest difficulty, whilst those of a complex 

 composition 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 divisi- 

 bility of matter in general, the existence of chemical proportions 

 removes every doubt respecting the presence of certain limited 

 groups or masses of matter which we have not the power of divid- 

 ing. The particles of matter called equivalents in chemistry 

 are not infinitely small, for they possess a weight, and are capa- 

 ble 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 instances according to the direction 

 and place, which the simple atoms take in the compound mole- 

 cules. 



When we compare the composition of organic compounds with 

 inorganic, we are quite n mazed at the existence of combinations, 

 in one single molecule of which, ninety or several hundred atoms 

 or equivalents are united. Thus, the compound atom of an or- 

 ganic acid of very simple composition, acetic acid for example, 

 contains twelve equivalents of simple elements ; one atom of kinic 

 acid contains thirty-three ; one of sugar thirty-six ; one of amyg- 

 dalin ninety ; and one of stearic acid 138 equivalents. The 

 component parts of animal bodies aro infinitely more complex 

 even than these. 



