IS 13.] On the Cauw of Chemlad Proporli^is. 449 



say, that it is composed of 1% atom of the first and 1 atom of 

 the second. One method of refuting- this objection would be to 

 consider tiie black oxide of iron as containing 4 atoms of 

 oxygen, the red as containing 6", and the intermediate oxide as 

 containing 5 : but in this case the analysis of Gay-Lussae is 

 incorrect. He should have obtained 3o'-S of oxygen instead of 

 3/8. But we are not at present acquainted with any example 

 ot a body containing 5 atoms of oxygen ; and I shall prove in 

 the sequel that the oxide in question cannot be considered as a 

 particular oxide, since it possesses all the characters of a com- 

 pound of the red and black oxides of iron. 



3. We have seen that an elementary atom cannot combine 

 with more than 12 elementary atoms. Inorganic nature has not 

 yet presented us with any body which is inconsistent with this 

 supposition : but among organic bodies such examples are very 

 frequent. It is in the study of the composition of organic bodies 

 that our knowledge of the laws of chemical proportions, and of 

 the electro-chemical theory, will one day reach that degree 

 of perfection which the human mind is capable of giving it. I 

 shall give the compositiou of oxalic acid as an example of the 

 constitution of an organic atom. 1 analyzed this acid by decom- 

 l>osing it, by distilling oxalate of had mixed with a quantity of 

 brown oxide of lead, and making the gaseous products pass 

 through muriate of lime, and then through lime-water. I re- 

 peated this analysis with so little variation, that I consider my 

 results as a close approximation to the truth. In neither of these 

 analyses did I obtain as much water as amounted to a quantity of 

 hydrogen equivalent to 1 per cent, of the acid : but we cannot 

 conceive an atom of oxygen to be united with a fraction of an 

 atom of hydrogen. We must therefore consider the small 

 quantity of hydrogen which we obtain as an entire atom. If we 

 admit water to be a compound of 2 atoms of hydrogen and 1 

 atom of oxygen, and carbonic acid of 1 atom of carbon and 2 

 atoms of oxygen, it follows from my analysis, that the atom of 

 oxalic acid is composed of 1 atom of hydrogen, 2J atoms of 

 carbon, and 18 atoms of oxygeii ; that is to say, that it consists 

 of an atom of hydrogen combined with 15 other atoms. 



If, on the other hand, we choose to consider the organic atoms 

 as consisting of an atom of compound radicle combined with 1 

 or more atoms of oxygen, and of course oxalic acid as composed 

 of an atom of radicle and 3 atoms of oxygen : the radicle in 

 that case will be a compound of 1 atom hydrogen -+- JJ atoms 

 carbon, and will remain equally inapplicable to the hypothesis 

 of atoms. It follows, likewise, that an atom of oxalic acid h 

 eleven times greater than an atom of sulphuric acid, and fifteen 

 times greater than an atom of potash : yet in the sup Tov.ibte of 



Vol. II. N° VI. 2 F 



