40 On Oxalic Acid. 



Now, in all compounds consisting of these ingredients, the 

 proportion of the different constituents may always be re- 

 presented by these numbers, or by multiples of them ; thus, 

 the composition of the following substances may be thus 

 stated : 





Oxygen. 



Hydrogen. 



Carbon. 



Azote. 



Water 



6 



+ 1 







Carbonic oxide 



6 



- 



4- 4-5 





Carbonic acid 



2x6 



- 



+ 4'5 





Carburetted hydrogen 



- 



2 X 1 



+ 4-5 





Oleflant gas 



- 



1 



+ 4-5 





Nitrous gas 



6 



- 



- 



+ 5 



Nitric acid 



2x6 



- 



- 



+ 5 



Nitrous oxide 



6 



- 



- 



4-2X5 



From the knowledge of this curious law, it is difficult to 

 avoid concluding that each of these elements consists of atoms 

 of determinate weight, which combine according to certain 

 iixed proportions, and that the numbers above given repre- 

 sent the relative weights of these atoms respectively. Thus, 

 an atom of oxygen weighs six, an atom of hydrogen one, 

 &c. Water is composed of one atom of oxygen, and one 

 atom of hydrogen ; carbonic acid of two atoms of oxygen, 

 and one of carbon, 8cc. This curious theory, which promises 

 to throw an unexpected light on the obscurest parts of che- 

 mistry, belongs to Mr. Dalton. I have elsewhere illustrated 

 it at considerable length*. 



The same law holds with respect to the salts. The acid 

 and bases always combine in determinate proportions. We 

 may affix numbers to all the acids and bases, which num- 

 bers, or their multiples, will represent all the combinations- 

 into which these bodies enter. Some of these numbers are 

 given in the following table : 



Sulphuric acid 33 Barytes 67 

 Muriatic acid 18 Soda 24 



Carbonic acid 16*5 Lime 23 



Nitric acid 17 Ammonia 6 



See System of Chemistry, iii, 424, &c. 3d edition, 



Thes-c 



