SIE B. C. BEODEB ON THE a\LCULUS OF CHEMICAL OPERATIONS. 

 1 volume of phosphorus-vapour, 



823 



and 



whence 



and 



m=2, mi=ly 



n =2, Til =4, 



a minimum ; and we have for the 



Symbol of phosphide of hydrogen a^<p. 

 Symbol of phosphorus , . . u^(p* 

 Assuming the density of phosphorus-vapour as 62, 



2+iw(<p)=62, 



Combinations of the Prime Factors a, |, 6, X, x, i^, P, "> and <p. 



5t2 



