190 On some Poinfs co?Tvected luilh i he Atomic Theory. [March, 



ought to be followed. The analysis of oxalate of lead is much 

 simpler, not liable to the same uncertainties, and susceptible of 

 greater exactness than the analysis of oxalic acid. We ought,^ 

 therefore, to be guided by it ; especially as it is corroborated by 

 various other very exact analyses, as those of oxalate of potash, 

 oxalate of ammonia, and oxalate of strontian. But if we adopt 

 this detercnination, and compare it with the analysis of oxalic acid, 

 we shall find that this acid must be composed of six atoms; namely, 

 three atoms oxygen, two carbon, and one hydrogen ; and its com- 

 position will be 



Weight. 



Oxygen 64739 or 3 atoms = 3*000 



Carbon 32'413 2 = 1-502 



Hydrogen 2-848 1 =0-132 



100-000 4-634 



Now this is the composition of the acid which I deduced some 

 time ago by comparing my own analysis of oxalic acid with the 

 composition of oxalate of lead as determined by Berzelius. 1 

 obtained for the composition of oxalic acid 



Oxygen 64 



Carbon 32 



Hydrogen 4 



100 



My experiment was conducted with great care, and I still con- 

 sider my result as nearer the truth than either that obtained by Gay- 

 Lussac and Thenard or by Berzelius. My excess of hydrogen 

 amounts to about one per cent., and was probably owing to the salt 

 whicli I employed in the analysis not being quite free from water. 

 Mr. Dalton has adopted tiie same constitution of oxalic acid with 

 the above, and probably he has been led to it by the same mode of 

 reasoning from which I deduced it. 



I shall take another opportunity of examining the other acids 

 analyzed by Berzelius, by applying to them the test of the atomic 

 theory. What I have here said is sufficient to show us that the 

 most cautious and elaborate experiments are not sufficient of them- 

 selves to make us acquainted with the composition of these intricate 

 bodies ; though such experiments afibrd us considerable assistance, 

 and, when compared with the structure of the salts as explained by 

 the atomic theory, will generally be sufficient to give us all the 

 information respecting the constitution of these acids which we can 

 expect to obtain. 



