1814.] Elements of Organic Nature are comlined. 327 



acid ought to contain three volumes of oxygen, or 15*975 x 3 =s 

 4 7-925. Accordingly analysis gives this result. It gives us, besides, 

 47*859 per cent, of carbon and 4'218 of hydrogen • so that suc- 

 cinic acid is composed of 



3 volumes oxygen 



4 carbon 



4 hydrogen 



It is in this manner, by consulting not merely analysis, but by 

 examining the compounds of which the substance is capable, that 

 we are enabled to unfold the laws of chemical proportions in 

 organic nature. Observations prove also clearly that in ternary and 

 quaternary oxides we need not look among the elements for one 

 which must of necessity be reckoned unity • though it may some- 

 times happen that only a single volume of one of the elements may 

 enter into the compound. 



It is then almost impossible to determine by analysis the number 

 of elementary volumes contained in the substance analysed. This 

 must always be done by examining the combinations which it forms 

 with other oxides, the composition of which is known. If a sub- 

 stance cannot be obtained in a state of combination, it is very 

 difficult, if not impossible, to determine its true composition ; 

 because when the number of volumes of one element is great, the 

 experiment can never be made with sufficient precision to determine 

 the exact number, unless we can find by other means the number 

 of volumes of one of the elements. 



The combustible radicles which constitute the ternary and qua- 

 ternary oxides are hydrogen, carbon, and nitricum. Hydrogen and 

 carbon constitute the ternary oxides of the vegetable kingdom. 

 They have all less or more of the characters of acids ; that is to 

 say, they combine with saline bases. The addition of nitricum 

 constitutes the quaternary oxides of which the animal kingdom is 

 chieily composed. They have, though not without exception, the 

 characters of bases ; that is to say, they have a disposition to com- 

 bine with acids. The more complete the organization becomes, 

 the more does the Dumber of elements increase. 



.Several organic bodies contain, besides, other elements, which 

 are just as essential to them as hydrogen and carbon ; but they 

 enter in infinitely small proportions; so small, indeed, that analysis 

 cannot with any certainty determine the relation between their 

 volumes and the number of volume- <>i the other elements. Such 

 are sulphur, phosphorus (perhaps likewise the muriatic and fluoric 

 radicles), potassium, sodium, calcium, iron, and sometimes silicon 

 and manganese. The combustible radicles occur often in form of 

 oxides in organic nature ; but most frequently they enter by the 



same manner of combination as hydrogen and carbon. 



\\ I n*i i making an analysis of blood. 1 proved (nog ago that the 

 bodies which constitute the ashes of the colouring matter of the 

 blood do not exist in the organic body in the same form and state as 



4 



