130 Remarks on the preceding Answer. [Feb. 



during the action of moist iodine upon phosphorus, I alluded 

 merely to your verbal statements ; and I will readily confess to 

 you that I did not understand a chemical theorem expressed in 

 such symbols as you employ. 



In the first place, in giving your symbolic statement of Berze- 

 lius's theory, you represent his superoxidum iodicum by I 3 , but 



he by I ; your symbol means 3 atoms of iodicum, not iodicum 



combined with 3 atoms of oxygen ; P is Berzelius's representa- 

 tive of phosphorous acid, consisting of phosphorus + 3 atoms of 

 oxygen; your symbol of P 1 , if it have any meaning, is that of 



1 atom of phosphorus. Again, you represent the " iodic acid 

 ofBerzelius" by P, which, according to him, means 2 atoms of 



iodicum ; his symbol is I. 



I observe also, that you suppose the phosphorous acid ofBer- 

 zelius to contain only 1 atom of oxygen, whereas he states it to 

 contain 3 atoms. On this subject 1 may remark, that you have 

 performed a feat on paper which Berzelius himself would be glad 

 to see reduced to experiment ; if you find that his phosphorous 

 acid is formed without the decomposition of the water, you 

 are of course able to present him with his imaginary iodicum in 

 an isolated state ; for it must have surrendered its 3 atoms of 

 oxygen to the phosphorus. 



The hydriodic acid of Gay-Lussac, which you allow to be 

 formed in this experiment, is not the iodic acid of Berzelius ; he 



terms it iodas hydricus,* and represents it by Aq I, and not 



by I, as he would do if it were mere iodic acid, and still less by 

 I 9 , as you have done, which, as I have already observed, means 



2 atoms of iodicum. 



In explaining Gay-Lussac's theory, you have employed H 1 to 

 express an atom of water ; whereas in your "right " statement of 

 the composition of sulphuric acid, you employ the word at full 

 length, thus; " S 1 -f water;" Berzelius, however, adopts Aq, 

 and if H' have any meaning at all, it designates one atom of 

 hydrogen. In order to represent the oxygen of the atom of 

 water, you separate the coefficient thus, J- ; while Berzelius 

 represents it by O, and 2 atoms of oxygen by O', but -i- s would 

 be rather an odd expression for the same meaning. 



I have now done with your symbols, and nearly with my 

 remarks. If the errors you have committed have produced any 

 effect upon me, it is that of confirming my utter dislike of symbolic 

 notation. When explaining the motives that induced you to adopt 

 an arrangement which to me appeared of a most extraordinary 

 description, you have attributed to it the advantage of train- 

 ing the student to scepticism or indifference in theoretical points ; 



* Essai sur la Theorie des Proportions Chimiques, Table, p. I IS. ■ 



