WITH THE MARINE ACID* 353 



Plummcrhasafcertainedby experiments, that 

 the weight of the white mercurial precipitate, 

 when thoroughly exficcated, is fomcwhat great- 

 er than that of the mercury employed in the 

 procefs*. 



When no more precipitate is occafioncd by 

 the addition of the folution of common fait, the 

 liquor poured oil* does not altogether lofe its 

 caullic property ; hence, therefore, it is fuppof- 

 c.d to poft'efs the virtue of removing fpots and 

 freckles on the face. If it is mixed with the wa- 

 ter of roles, lillies, and beans, &c. it becomes mil- 

 ky, and is reckoned among the remedies for af- 

 fcclions of the face ; and has on that account ob- 

 tained the name of cofmetic mercury f. Its a- 

 crid quality arifes from the mercury dittblved in 

 it, which may be collected in a copious fcdimcnt 

 by pouring into it fixed or volatile alkali. Tliis 

 circumilancc has been already obfcrved by 

 Barchuicn {; and if we are to give credit to 

 Junker, fcarce one-fourth is precipitated, when 

 equal weights of conunon fait and mercury arc 

 taken for this preparation J. The fad has been 

 frequently remarked, and the feverai pharma- 

 copoeias have, in confequence of it, adopted the 

 pradice of mixing the fpirit of fal ammoniac 

 7, with 



* Obfcrvations of the Society at Edinburgh, Vol. I. 



f I. T. Carthcufcr in Pharmacia. 



J Elcm. Chym. 



Confj). Chcmir. 



