42 On Oxalic Acid. 



Oxygen 



61 



Carbon 



34 



Hydrogen 



5 



IOO 



numbers which do not indeed exactly correspond with the 

 result of the preceding analysis, but which approach suffi- 

 ciently near it to give the reasoning employed considerable 

 probability at least, if it does not lead to certainty. 



We may now examine the decomposition which takes 

 place when oxalate of lime is exposed to heat. Let an atom 

 of oxygen be u>, an atom of carbon c, and an atom of hy- 

 drogen ft. An integrant particle of oxalic acid may be repre- 

 sented by 4 W -f 3 c + 2 ft. We may represent the com- 

 position and weight of an integrant particle of each of the 

 substances into which oxalic acid is decomposed by heat, 

 by the following symbols and numbers : 



Carbonic acid - 2w -f c weight 16-5 

 Carburetted hydrogen c + 2 h - 6-5 



Carbonic oxide 



- 



IV -f c 



- 



10' 5 



Water 



- 



w + ft 



- 



7 



Charcoal 



- 



c 



- 



4-5 



We may now conceive three particles of oxalic acid to be 

 decomposed at once, and to resolve themselves into these 

 substances, in the following proportions : 



4 particles of carbonic acid = 8 iu -f 4 c 



Q particles of carburetted hydrogen = - - 2 c -f- 4 ft 



2 particles of carbonic oxide = 2 w + 2 c 



2 particles of water - - = 2a/ - - -f 2ft 



1 particle of charcoal - = - - 1 c 



Total 12 tv -f 9 c + 6ft 



3 particles of oxalic acid - —Wiu + Qc + Qh 



We see that such a decomposition is possible, it remains 

 only therefore to see whether the weights of these substances, 

 vhich result from this hypothesis, correspond with the pre- 

 ceding analysis. Now, 



4 particles 



