466 On phlogiston. 



One drachm of the flowers of zinc and twelve grains of 

 red hot coal, which had ceafed to yield air, being expofed to 

 a red heat gave fifty-eight ounce meafures of hydrogenous 

 gas, every portion of which was mixed with fome carbo- 

 nic acid. 



One drachm of the precipitate of zinc, from a folution 

 of white vitriol by ammoniac, expofed to a red heat half 

 an hour, when mixed while red hot, with red hot coal, 

 which had ceafed to yield air, gave fourteen ounce mea- 

 fures of inflammable air, mixed with carbonic acid. 



The flowers and precipitate of zinc in thefe cafes, fup- 

 plied the coal with water which was decompofed. The 

 metal was not revived. 



SECTION III. 



Of Finery Cinder or the Scales af Iron, 



The antiphlogiftic chemifts confider the fcales, which the 

 blackfmiths fl:rike off from red hot iron, to be iron partially 

 oxygenated. 



On the contrary Dr. Prieftley fuppofes, that when iron 

 is heated in oxygenous gas, it parts with its phlogiflon, 

 and is converted into a fubflance refembling finery cinder, 

 but he will not allow that the air which difappears in this 

 procefs, is imbibed by the iron, but only the water which 

 was its bafe, while the oxygenous gas, he fays, always 

 goes to form the fixed air which is found in the experi- 

 ment. 



He declares that the quantity of carbonic acid, is quite 

 fufficient to take all the oxygenous gas that difappears in the 

 procefs. 



That the Dodor's ideas are not juft on this fubjedt, we 

 have the jnoft conclufive evidence. 



If 



