Chap." 31.] Means of difcovenng Lead in Liquors. 1 89 



tage*: Boil together, in a pint of water, an ounce of 

 quick lime and half an ounce of flowers of brimrlone, 

 and when the liquor, which will be of a yellow colour, 

 is cold, pour it into a bottle, cork it up, and referve 

 it for ufe. A few drops of this liquor, being let fall 

 into a glais of wine or cyder containing lead, will 

 change the whole into a colour more or lefs brown, 

 according to the quantity of lead which it contains ; 

 if the wine is wholly free from lead, it will be rendered 

 in fome meafure turbid by the liquor, but the colour 

 will be rather a dirty white than a blackim brown. 



In general, a folution of common liver of fulphur 

 will precipitate the lead, but unfortunately iron as 

 well as lead is precipitated by both thefe tefts, and it is 

 faid that many honetl wine merchants have been ruined 

 by this means, by having iinjuftly fallen under the 

 fufpicion of adulterating their wines with lead. M. 

 Hannemann has publifhed a paper in the Journal de: 

 Phyfique, in which he affures us, that the following 

 liquor, whilft it does not precipitate iron, will preci- 

 pitate lead and copper of a black colour, and arienic 

 of an orange. Mix equal parts of oyfter (hells and 

 crude fulphur in fine pov/der, and put them into a 

 crucible ; apply a brifk fire in an air furnace, fo as to 

 make the crucible of a white heat for about fifteen 

 minutes. The mafs, when cold and powdered, fhould 

 be kept in a bottle well corked. To prepare the 



* Bifhop Watfon. This excellent and truly refpeftable author, 

 tliis great ornament of the Englifh church, will. I flatter myfelf, 

 'forgive the very free and frequent ufe I have made of his incom- 

 parable Eflays. He has ever been 



*' Mihi magnus Apollo." 

 " My guide, philofopher " 



and, if I was not afraid of prefuming too far, I would add the con- 

 clufton of that well known line. 



liquor, 



