824 



SIR B, C. BEODIE ON THE CALCULUS OF CHEMICAL OPERATIONS. 



(10) Symbol of Arsenic. — The density of the chloride of arsenic has been determined 

 by Dumas, the density of arsenic-vapour by Mitsciierlich. 



Four volumes of the chloride of arsenic are decomposed into 1 volume of arsenic 

 and G volumes of chlorine. 



Hence, putting a'"-)^'f' as the symbol of the unit of chloride of arsenic, and oiP-j^'f^ as 

 the symbol of the unit of arsenic, and ay^^ as the symbol of the unit of chlorine. 



and 

 whence 



4m=6+«, 4nii=12+«j, 4^2=^2. 



The minimum solution of these equations gives 



m=2, n=2, 



mi=3, «i=0, 



m2=l, «2='^5 

 and we have, as thus determined. 



Symbol of arsenic a^^, 



Symbol of terchloride of arsenic . . ct,^'/,^§. 



Assuming 150 as the density of the vapour of arsenic, 



w(g)= 37. 



Combinations of the Prime Factors a, |, ^, p^, . . . . and §. 



(11) Symbol of Mercury. — Assuming 100 as the density of the vapour of mercury, and 



