SILICON. 169 



which the iron contained. The iron was then 

 peroxydized, precipitated by ammonia, heated to 

 redness, and weighed. The iron and carbon 

 deducted from the original weight of the iron, 

 gave the weight of the silicon which had been 

 united with it. This silicon weighed 127 parts, 

 but the silica obtained when the specimen was 

 treated with muriatic acid, amounted to 335 

 parts. Now, 335 127 = 208 = the oxygen 

 combined with 127 parts of silicon. But other 

 experiments gave him silica composed of 



Silicon 5 1-5 and 52-25 

 Oxygen 48-5 and 47*75 



These experiments were repeated by Stromeyer,* 

 who obtained for a result 



Silicon 46-0069 

 Oxygen 53-9931 



Now, the mean of these two sets of experiments 

 gives us the composition of silica as follows : 



Silicon 49-9189 or 0-99^6 

 Oxygen 50-0811 1-0000 



100-0000 1-9966 = atomic weight of Gives 

 silica, which approaches exceedingly near 2. ^ 



silica. 



Berzelius, in his essay on Chemical Propor- 

 tions, and in the second edition of his Larbok i 



* Gilbert's Annalen. XXXVIII. 321 



