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fore fuch veflcls are pcrfedtly fafe ; while the glazing 

 of ordinary earthen-wzTQy confiding of a calx of 

 lead, is eafily adled upon by acids, and yields a 

 iioxious quality. 



The fame remark is in fome meafure applicable 

 to vefTels lined with tin. l?ure block-tin, it is 

 true, gives no impregnation to vinegar or acid 

 juices, but the generality of tinned veflels contain 

 a confiderable alloy of lead, befides what is ufed 

 in the folder. This is very diftinguilhable even by 

 rubbing a finger over them, which will foon ac- 

 quire a blackifli hue from the lead; a circumfirance 

 worthy notice, as too much confidence is generally 

 placed on the fafety of tinned veflels. Not to 

 mention the danger of the tin lining foon wearing 

 ofi^, and leaving a copper furface expofed. Hence 

 the fatal accidents that have enfued from acid 

 iauces and gravy foups {landing too long in fuch 

 vefTels, and acquiring thereby an impregnation 

 doubly dangerous. For here the poifon of lead, 

 and verdigris, combine their united forces to un- 

 dermine the human frame 1 



The Dutch have been accufed of corredling the 

 rancidity of oils, and even butter, by pouring melted 

 lead into them. If this be true, the ordinary prac- 

 tice of preferving faked- butter or hog's lard in glazed 



earthen 



