370 Dr. Henry*s Analysis of a erysinllixed Compound [May, 



subject under various aspects, it appears to me most probable 

 that the following is the constitution of the solid, the atomic 

 numbers being adapted to the hydrogen scale. 



Sulphuric acid, 5 atoms (40 x 5) 200 



Hyponitrous acid,* 1 atom 38 



Water, 5 atoms (9 x 5) 45 



Weight of its atom 283 



Or in 100 parts, 



Sulphuric acid 70-67 



Hyponitrous acid 13'42 



Water 15-91 



100-00 



The excess of water obtained by experiment over the theore- 

 tical proportion, may be ascribed to the solid having imbibed 

 water in addition to that which is essential to it in a crystallized 

 form. 



The changes which the solid undergoes when brought into 

 contact with water, are probably the following : — An atom of 

 hyponitrous acid (which it is convenient for our present purpose 

 to view as constituted of an atom of nitrous gas united with an 

 atom of oxygen) is decomposed ; the atom of nitrous gas 

 escapes ; and the atom of oxygen, uniting with a contiguous} 

 atom of hyponitrous acid, composes an 

 atom of nitrous acid. This will be 

 better understood with the aid of the 



annexed symbols, (jj representing the 



atom of nitrogen, and \_) that of oxy- 

 gen. The two upper symbols denote (-""yTY^ 

 two atoms of hyponitrous acid, and K^/'A/^ 

 the two lower ones express an atom of 



• The existence of hyponitrous acid (sab-nitrous acid of Dalton, acirfe pernitreux of 

 Gay-Lussac), though it has been questioned by one or two chemical philosophers of 

 great name, I consider as established by a variety of facts and arguments, which I have 

 fully statf d elsewhere (Elem. of Chem. 1 0th Edit. i. 3 1 2, 3 1 8). No doubt on the sub- 

 ject can, it appears to me, exist in the mind of any one who attentively peruses M. Gay- 

 Lussac's excellent memoir, in the first volume of Annales de Chiniie et de Physique, on 

 the Compounds of Azote and Oxygen. The series of those compounds, which would 

 otherwise have been an interrupted one, is completed as follows : 



Vols, of Atoms of Atomic wt. 



nit. oxy. Forming. nit. ox. (nit. 14, ox. 8.) 



Nitrous oxide (protoxide), 1 + 0*5 .... 1 vol 1 + 1 .... 22 



Nitrous gas (deutoxide). . 1 + 1' .... 2 vols I + 2 .... 30 



Hyponitrous acid 1 + 1*5 .... 1 vol 1 + 3 .... 38 



Nitrous acid 1 + 2- .... 1 vol 1 + 4 .... 46 



Nitric «rid , I + S-6 .... 1 vol 1 + fi .... M 



