21 S Procefs for Thming Copper Vejfels 



fore, only two mcafures that can be fnppofed to be produced 

 from the muriatic acid gas; a quantity too fmall to afford 

 grounds for fuppofing them to arife from decompofed acid. 

 Exper. 13, Dry carbonated hydrogenous gas 132 meafures,- 

 mixed with dry muriatic gas - 108 



by 200 fhocks, expanded to - 268 

 Part of this gas was then transferred to another tube, and 

 the proportion of permanent gas afcertaincd. Through the 

 remainder, 150 additional fliocks were pafled, before the 

 amount of the gas thus evolved was determined. In both, 

 it bore exaftly the fame proportion to the original gas;^ 

 •which fliows that, by continuing the cleftrifation, no fur- 

 ther cffc£ls wefe produced. 



[To be eofitinued.] 



IV. New Proeefs for Tinning Copper and other Vejfels in a 

 durable Mcmner. Bj' M. Busciiendorf, of Leipjic *. 



JL HAT copper and brafs vcflcls cannot be ufcd with 

 fafety in cooking viftuals or for holding articles of food, and 

 particularly thofe which contain acids, is well known. It is 

 alfo well known that the tinning applied in the ufual man- 

 ner is not durable, being foon worn away l>y cleaning, and' 

 on that account muft be frequently renewed. Some, there- 

 fore, have propofed enamelling for kitchen utenfils of cop- 

 per; which, indeed, would anfwcr exceedingly well, and be. 

 much fafer for the health than impure tin mixed with lead, 

 often employed for tinning: but, unfortunately, enamel is 

 too dear, and readily breaks when the veflel receives the leaft 

 blow; which cannot always be avoided f, 



''■ From Journal fur FalJrik, Mimufndur, unci H(VuUu':g. Odlober 1799. 



f Articles that would come high when made fingly, may be afforded 

 at a low rate when manufaftured on an extenfivc fcalc. Cooking utenfii; 

 lined with a vitrified glazing, are now commonly fold in many.fhops iii 

 London, and at a moderate price. It r,'ould be as reafonablc to objeft 

 to the ufe of earthen-ware 01; china, becaufe they may be broken by 

 blows, as to maXe this an objeftion againft the \iic of glazed kettles. — 

 Ebit. 



The 



