1 8 6 Sugar of Lead. [Book VI. 



pain from the Devor.fhire colic, lofe the entire ufe of 

 their limbs, or gradually pine away by a wafting, ma- 

 rafmus. In a well regulated community fuch works 

 ought to be entirely prohibited, or at leaft only car- 

 ried on by the word of felons, whofe lives would be 

 other wife forfeited. 



Lead, after being thus reduced to the ftate of cerufe 

 by the fumes of the-acetous acid, may be eafily diflblved 

 in the fame acid in a fluid (late, and the faline matter 

 thus formed, is then called, from its fweet but aftrin- 

 gent tafte, fugar of lead, 



To have this fait of lead in the form of tranfparent 

 cryftals, it is necefiary to ufe much acid j if there is 

 not a redundancy of acid, moft of the cryftals are 

 fmall and mealy. This may be remedied by difiblv- 

 ing them again in diftilled vinegar, and repeating the 

 cryftallization. In this manner fo much of the acid 

 may be united to the metal as to change the appear- 

 ance of the fait to that of an oily fluid. This metallic 

 fait, like others, may be decompofed by an alkali. In 

 all thefe cafes the precipitates of lead are white, but 

 the calces are coloured. 



The faccharum faturni, or fugar of kad, may be 

 decompofed by heat alone, for, when expofed to a 

 gradual heat, the acid rifes in a very concentrated 

 ftate. This procefs is attended with the remarkable 

 'phenomenon of the production of a quantity of ardent 

 fpirit *. To underftand the caufes of this phenome- 

 non, it is only neceflary to be informed that alcohol, or 

 ardent fpirit, is a combination of hydrogen, charcoal, and 

 a fmall quantity of oxygen. Now all thefe principles 



* By the pV!ogi(Hc hypothecs tins fact admitted of explanation, 

 by fuppofing that the principle of inflammability of the metal 

 combined itfelf with a portion of water, contained in the acetous 

 acid, arid thus formed alcohol, or fpirit. 



fcxift 



