corrosive SuUhnate in tlie humid IVay^ 231? 



crystallization the two salts mixed^ and that no other means. 

 of separating them remained hut by alcohol. I shall pass 

 over in silence the operations, which were attended with 

 more or less success in this point of view, and. describe 

 only the process which I definitively adopted. 



r introduced into a tubulated retort two ounces of mer- 

 cury and three ounces three gros of concentrated sulphuric 

 acid ; 1 then adapted to the retort a receiver, without luting 

 it, and made a pretty strong fire. Daring the solution there 

 was diseno-aiTcd a very considerable quantity of sulphureous 

 gas. When nothing remained in the retort but a white 

 mass, I added a solution of b\ ounces of marine salt in six 

 ounces of water, and exposed the mixture to strong ebulli- 

 tion for half an hour. A complete solution took place. I 

 filtered the liquid while still in a state of ebullition, put it 

 into a retort, and distilled it to dryness. On the remaining 

 mass I poured IC ounces of alcohol, and caused it to digest 

 for some hours. I then decanted the liquid from ofl' the 

 residuum, filtered it again warm, and put it once more into 

 the retort after I had \vashed it, taking care not to spread 

 any of it in the neck of the retort, and distilled it to dry- 

 ness. I must here remark, that the distilled liquid, which 

 at first had the colour of Malaga v^-ine, assumed, after tlie 

 solution was concentrated, the colour of water de Rabel ; 

 and the saUne mass, after the complete evaporation of the 

 alcohol, was exceedingly white. Lime water made no change 

 in the colour of this liquid. 



I poured over the mass in the retort 1 2 ounces of water ; 

 I boiled it to solution, and, having filtered the liquor, ex- 

 posed it to crystallize. Very beautiful crystals in the form 

 t)f elongated prisms were deposited. I then poured over 

 tlic residuum eight ounces of new spirit of wine, and agaia 

 obtained a considerable quantity of corrosive sublimate. The 

 distilled liquid, after being rectified on half an ounce of pot- 

 ash, was perfectly pure. 



By employmg this method, corrosive sublimate, in my 

 opinion, will cost one-half less than by VVestrumb's pro- 

 cess. Sulphuric acid costs only one-third of what the nitric 

 acid does ; and there is no comparison between the price 

 of pure nuu-iatic acid and that of marine salt. 1 therefore 

 flatter myself that this method will meet with a favourable 

 reception. 



P 4 XXXIX. Ob' 



