K X-rays of Silver in Gases and Gaseous Mixtures. 387 



and Collier's values for the total absorption coefficient. The 

 wave-length chosen is for the K a doublet. 



Fig. 3. 



lOfffp 



Log * (AM. for k x J 



From the slopes of the lines the constant x, of: the equation 

 t/p = A\ :l \ has the values 2'60 for methyl iodide, 2*80 for 

 sulphur dioxide, and 3*13 for air and carbon dioxide. 



(2) Absorption in Mixtures. 



Three mixtures were used — air and sulphur dioxide, carbon 

 dioxide and sulphur dioxide, methyl iodide and air — and, 

 in addition, the absorption in the mixture sulphur dioxide 

 and hydrogen (equal volumes) was compared with that in 

 the mixture, sulphuretted hydrogen and oxygen (equal 

 volumes) ; each of: these latter mixtures has the same number 

 of atoms of each element but the chemical combination is 

 different. 



In the case of any mixture the absorption, if additive, 

 will be in accord with the relation 



-dhVi + HP^/F 

 JL = li • e 



i.e., (/x 1 p 1 + ^ 2 /) 2 ) = 34*4 (log 10 Ti— log 10 I 2 ). 



2 2 



