1825.] 



Three new Salts of Soda, 



439 



pliate of soda, there remain 8-03. Now 8*03 is very nearly the 

 third part of 25*42. Thus the constituents of the salt are, 



Sulphuric acid 25-42 or 7-31 



Soda 13-91 4-0 



Loss 0-67 0-19 



40-00 



If the loss be sulphuric acid, as is not unlikely, then the salt 

 is anhydrous, and its constituents are, 



1 J- atom sulphuric acid 7-5 



1 atom soda , 4'0 



lT-"5 



As the liquid from which these crystals were obtained con- 

 tained a quantity of common salt, I thought it possible that 

 muriatic acid might have formed a constituent of the salt ; 

 but when a dilute solution of the crystals was tested with nitrate 

 of silver, no precipitate whatever fell. This shows that the salt 

 was free from muriatic acid. Its only constituents that I could 

 detect are sulphuric acid and soda. 



2. Bisulphate^of Soda, 



If we dissolve glauber salt in dilute sulphuric acid, and, after 

 concentrating the solution sufficiently, set it aside, a number of 

 crystals shoot in it, which are in transparent prisms, and at first 

 sight bear a close resemblance to those of common sulphate of 

 soda. 



These crystals do not sensibly dehquesce when exposed to the 

 air (at least the deliquescence is very slow). But when left upon 

 blotting paper, that paper soon becomes moist, and continues 

 so. The salt was four times successively transferred to dry 

 paper ; but the same moistening effect took place upon each. 

 From this I am led to conclude, that the salt slowly attracts 

 water from the atmosphere. 



The crystals when formed in favourable 

 circumstances were four sided prisms 

 terminated by an oblique summit as re- 

 presented in the margin, sensibly the 

 same as the crystal of sulphate of soda ; 

 though in all probability the inclinations 

 of the faces differed a little ; but none of 

 them were bright enough to admit of 

 measurement by the reflective goniometer. 

 All the crystals observed were four-sided 

 prisms. In some the terminating plane 

 had the form of «, figure B, though the 



