WITH THE MARINE ACID. 



but when, by tlicfo alone, corrofive cannot be 

 converted into fwect mercury, it is very plain, 

 that the addition of quick-filvcr is necefTary; 

 unlcfs it is contended, that, by fublimations 

 in a greater number than what have hitherto 

 been attempted, corrofive may be changed into 

 fweet mercury. There is, no doubt, a certain 

 mutual relation in the weight of the acid and 

 of the quick-filver, which has not hitherto been 

 accurately defined ; although Lcmery by his 

 experiments feems to evince that the ratio is 

 as i to 61. 



Sweet mercury held in the fun, is, in amort 

 time tinged with a nob feu re colour*. In the dark, 

 too, as obfcrvcd by Schcelc, it fhines if rubbed; 

 which property, however it lofes, by repeated 

 fublimations. By this means, therefore, it may 

 be found out how often it has been fublimed. 



What is commonly laid, that gold is not 

 made pale by friction with fvvcet mercury, is 

 true ; but by this experiment, however, the 

 pcrfedion of this fait cannot be known ; for e- 

 ven by corrofive mercury, if well prepared, the 

 colour of gold is not changed. But fince, by 

 the addition of too much quick-filver, it con- 

 tains, after the firft fublimation, many metallic 

 globules; and that gold rubbed with it may by 

 this means be whitened, from hence this vulgar 



error 



* Ntaman. Pricl. Chera. 



