TIN. 401 



4. When thin plates of pure lead are intro- chloride of 

 duced into dry chlorine gas, the gas is gradually 

 absorbed and the lead converted into a white 

 matter, which is a chloride of lead. This chlo- 

 ride is easily obtained by mixing together solu- 

 tions of nitrate of lead and of common salt : 

 small brilliant crystals precipitate, which, when 

 heated in a close vessel, melt and assume the 

 form of a greyish matter, formerly distinguished 

 by the name of plumbum corneum. I find, by a 

 careful experiment, that 13 grains of lead, when 

 converted into chloride, weigh 17*5 grains. 

 Hence, it is obvious that this chloride is com- 

 posed of 



1 atom lead . . 13 



1 atom chlorine . 4-5 



17-5 



SECT. III. 



OF THE ATOMIC WEIGHT OF TIN. 



TIN is a metal which forms two different oxides, Oxides of 

 when it combines with oxygen. The protoxide ir 

 may be obtained by dissolving tin in strong mu- 

 riatic acid (taking care to exclude all access of 

 atmospheric air to the inside of the small retort in 

 which the process is going on). When the muri- 

 atic acid is saturated with the tin, the liquid must 



Voi. I. Cc 



