g", Nuiv Process for making Cinnahar in the Humid Way. 



fufFer tire produft to acquire its whole perfeftion on the evaporating furnace, but to take 

 it in time from the fand-bath, and leave it for three or four days in a degree of heat equal 

 to that of the (love of an apartment after it has been heated for two or three hours. Caic 

 muft be taken to add a few drops of water, and to agitate the mixture from time to time. 

 By this precaution, the difagreeable event of feeing the colour pafs from red to yellow, and 

 often to brown, is avoided, as well as the fubfequent labour and expence of trituration with 

 mercury, and additional liver of fulphur. 



8. Before the cinnabar is edulcorated, it maybe left to become almoft perfedly dry by 

 the heat of the ftove -, by which means the colour will acquire the mofl. brilliant tint. 



After this account of the produ£lion of cinnabar in the humid way, I fhall fpeak of the 

 'edulcoration and drying of this colour, which have prefented phenomena of the grcateft 

 importrcice to the fabrication iti the large way, and are alone fufficient to fecurc real ad- 

 vantages to the fpeculator in this article. 



Ha,ving obtained ten ounces of cinnabar, I poured twenty pounds of boiling water upon 

 it ill a large eartlien jar, for the purpofe of difengaging the liver of fulphur. At that mo- 

 ment the liquid Was obfcured and became abfolutely black. I {lightly agitated the mixture. 

 The cinnabar very fpeedily fell to the bottom, and permitted me to decant this black li- 

 quor, of which I fhall hereafter fpeak. After having poured other water upon the cinna- 

 bar, which was confiderably beautiful, it acquired a flight yellow colour. After the 

 fettling of the colour, I decanted it, and continued to edulcorate until the decanted water 

 had neither the faline fulphureous tafle, nor hepatic fmell. 



When I had" poured for the lad time five or fix pounds of boiling water on my colour, 

 I agitated it ftrongly, and poured it out into a veflel of cryftal glafs. A plentiful depofition 

 of colour was made in an inflant. It was not bad, but did not poflefs the brilliancy of the 

 particles which flpaced in the water above this depofition. I agitated the water very 

 flightly, that it might become more highly charged with colouring matter, but not fo much 

 as entirely to derange the mafs which had fubfided. I rapidly decanted the liquid part into 

 another veflel. The mofl; denfe portion remained at the bottom, and on the fides of the 

 firfl: glafs, and was of a very beautiful colour. I repeated this wafli in g four times with the 

 fame precautions, taking care always to pour the liquid part haftily into another veflel. 

 The refidue of the lafl; waftiing was entirely brown, and the tints of my cinnabar were beau- 

 tiful in the fame order as I had obferved in the decantation. That is to fay, the colour in the 

 firfl vefltl was more brilliant and lefs deep than in the fecond, and fo of the others. This 

 experiment fhowed not only that wafliing adds to the beauty of the cinnabar obtained by, 

 the procefs of KirchofF, but that it is poflTible, more efpecially in works on a large fcale, to 

 obtain a great variety of tints by mixture, without admitting any foreign colour or ma- 

 terial. 



After having thus obtained different cinnabars by wafliing, I dried them on a furnace 

 flightly heated, and found them more or lefs deep, but generally very good. They did not, 

 however, poflefs the fire of fuch cinnabars as inclined to a yellow colour. I put thefe co- 

 lours into capfules of paper, and left them for fome days on the fame flove, which had 

 continued to be regularly heated. At the end of this time, upon opening my papers it 

 appeared to me that the colour was improved; and had in particular become more lively 



4 thaa' 



