Chemistry. ] 8S 



Sulphuric acid, 5 atoms, (40 X 6) - - 200 



Hyponitrous acid, 1 atom, 38 



Water, 5 atoms, (9X5) - - - 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 theoretical pro- 

 portion, is 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 supposed, by Dr Henry, to be the following : — An atom of hy- 

 ponitrous acid (regarded for the sake of convenience 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 con- 

 tiguous atom of hyponitrous acid, composes an atom of nitrous acid. 



" The crystalline solid which has been above described, is probably 

 identical with that obtained many years ago by MM. Clement and De- 

 sormes, (An. de Chimie, xlix. 334,) by mingling in a glass ballooD, sulphu- 

 rous acid, nitrous gas, atmospheric air, and aqueous vapour ; and also with 

 a similar compound, afterwards formed by M. Gay-Lussac, by adding to 

 sulphuric acid the product of the distillation of nitrate of lead, which he 

 considers as chiefly hyponitrous acid, (An. de Chimie et de Phy. i. 407.) 

 It furnishes another example, in addition to those before known, of a weak 

 acid serving as a base to a more powerful one. The combinations of fluoric 

 acid with silica and boracic acid are familiar instances ; and M. Berzelius 

 has lately discovered others in the compounds of fluoric acid, with the 

 columbic, titanic, tungstic, and molybdic acids. These, however, differ 

 from the compound of hyponitrous and sulphuric acids, in possessing great- 

 er permanency, so as to form with bases distinct genera of salts, entitled 

 to the names of fluo-titanates, fluo-columbates, &c. ; whereas the com- 

 pound of sulphuric and hyponitrous acids is instantly decomposed by con- 

 tact with a base, and the salts obtained are identical with those which 

 would have been formed, if those acids had been separately united with 

 the same base." — Annals of Philosophy for May 1826. 



termined the proportion of air contained in these waters by boiling them. 



Grain Measures. 

 18000 grain measures of canal water (in winter) yielded 480 or j=-j 

 Filtered river water, drawn in the city of Glasgow from 



the pipes of the Cranston Hill Company - 454 



Filtered river water from the pipes of the Glasgow Water- 



i 



59.65 



Company - - - . - 450 



Water taken directly from the river Clyde, somewhat swol- 

 len by winter rains - - 505 



•10 



i 



