}~g PURIFICATION OF CAMPHOR. 



II. 



On the Purification of Camphor by Means of Potash. In a 

 Letter from a Correspondent. 



To Mr. NICHOLSON. 

 SIR, 



Camphor pu- Jjj ROM an idea of pure pojash having a greater affinity 

 potash- *° r nxe d °il s > t nan tne essential ones, and considering cam- 



phor as one of the latter in a concrete state, I was induced 

 to try its effects on some, which, though not the unrefined 

 camphor of commerce, was very impure, and possessed con- 

 siderable empyreumatic smell. After several experiments 

 with mixtures of it, different fixed oils, and sand (in order 

 to divide the particles), I found, that, when sublimed with a 

 small admixture of pure potash, the oily particles and em- 

 Subcarbonate pyreumatic smell were detained by the alkali. The subcar- 

 nie ectua . donate does not answer the purpose, because in that state the 

 affinity of potash for oils is less than when entirely deprived 

 of carbonic acid. 

 6 p. camphor, T wo drachms of camphor with considerable empyreuma- 

 S olive oil, 24 tic smell, and dirty, w^re mixed with one of olive oil, and 

 ^"astTmixed e ig nt °f sand; after which twenty grains of pure potash 

 and the cam- were added, and heat applied ; but though it was greater 

 phor subli- t|j an J s necessary for its sublimation, the product was per- 

 fectly free from empyreumatic smell, and a little whiter than 

 it generally is. 



Substituting linseed oil produced no alteration in the pro- 

 duct ; and supposing, that the fixed oily panicles of cam- 

 phor are not more liable to render it empyreumatic than 

 those employed, which did without the addition of the al- 

 kali, I take the iiberty of submitting this to your perusal, 

 and am, 



Sir, yours, &c. 



PHILOCHEMICUS. 

 Jan. 4, 1809. 



