€00 The Earl of Berkeley and Dr. C. V. Burton on 



Symbols used throughout this communication. 



For the solution : — 



w is the specific volume o£ the solution. 



s 1 is the decrease in volume of a large mass of solution 



when one gram of solvent is withdrawn from it ; 



s 2 is the corresponding quantity for the withdrawal of 



one gram of solute. 

 Ci is the number of grams of solvent in one gram of 



solution : c 2 is the corresponding quantity of solute. 

 F 1 is the osmotic pressure when the solution is in osmotic 



equilibrium with the pure solvent ; P 2 is the osmotic 



pressure when it is in equilibrium with the solute. 

 p is the pressure on the solution. 

 O is the total pressure of the mixed vapours in equilibrium 



with the solution. 

 G is the gravity potential. 



For the solvent : — 



u is the specific volume of the liquid. 

 q 1 is the pressure on the pure solvent. 

 7r 0o is the vapour-pressure when the solvent is under the 

 pressure of its own vapour. 

 v is the specific volume of the vapour. 



For the solute : — 



y is the specific volume of the liquid solute. 

 q 2 is the pressure on the pure liquid. 

 </> 00 is the vapour-pressure when the solute is under the 

 pressure of its own vapour. 

 z is the specific volume of the vapour. 



Where necessary, the particular vapour-pressure which is 

 under discussion will be identified by the addition of a suffix 

 denoting the pressure on the liquid ; the specific volume of 

 the vapour will be identified by a suffix denoting the pressure 

 on the vapour. For example : — 



7r q is the vapour-pressure of the solvent when there is a 



pressure q x on the solvent. 

 tt p is the vapour-pressure of the solvent in the solution 



when there is a pressure p on the solution. 

 77V is the vapour-pressure of the solvent in the solution 



when the solution is under pressure it. 

 z<p is the specific volume of the solute vapour when the 

 pressure on the vapour is <£. 



