ON THE OSMOTIC PRESSURES OF CALCIUM FERROCYANIDE SOLUTIONS. 333 



(1) that the salts in solution are associated* into double molecules, and these are 

 ionised, or (2) that the salts are ionised single molecules, and the ions are themselves 

 aggregated into larger complexes. 



026 



O24 



Ordinates are Che equivalent conductivities. 



Abscissae are the gram equivalents per litre of solution. 



Curve (I) refers to the calcium solutions . 



(2) 



strontium 



(I) 



018 



O16 



1-0 



1-5 



2-0 



2'5 



3-0 



Diagram 1. 



The first hypothesis is the more simple (it admits of a suitable chemical formula 

 being postulated), and if by its aid we can explain the facts, it will not be necessary 

 to consider the second. 



Assuming, then, that the molecules are double, we shall get the following tables, in 



* Cp. RAOULT (" Tonometrie," ' Scientia Series,' No. 8, p. 90) on the association of the sulphates of 

 divalent metals as evidenced by the lowering of the vapour pressures of the solutions. 



