HISTORY OF THE ATOMIC THEORY. 



201 



elements which produce with acids a very violent heat when 

 freed from their air, for example, lime and magnesia, by A , 

 as the sign of fire. 



" B. Before we set down the quantitative progression in the 

 case of vitriolic acid, we must first inquire if the quantity of 

 alumina in neutral alum belongs to this series; it is 1053. 

 Let us subtract 526 from 1053, and we obtain 527 ; now 527 = 

 640—13=6.90—13, and consequently 1053=5264-6.90—13. 

 But as the series determined by vitriolic acid proceeds by the 

 uninterrupted odd numbers, and no neutral alum can be found 

 in decomposing by double affinity, the quantity 5264-6.90 — 13 

 does not belong to this series. We must take it, however, in 

 the meantime into the series, because it belongs to the quan- 

 ities which enter into neutrality. We shall, however, put 

 such in brackets, as must happen when considering the quantity 

 of alumina in common alum, if it is not a legitimate member 

 of the series, and capable of double affinity. 

 2D 



