260 



The Earl of Berkeley on Solubility and 



The curves AE, FM, DG, and HN in fig. 4 represent 

 the definite information that theory and such experiments 

 as have been made give us. 



Dealing with the ordinary osmotic pressure first ; the 

 curve starts from A as a straight line (Boyle's law) and 

 passes upward concave to the ordinate through A (the curve 

 is given this form because, hitherto, no cases of convexity 

 have been observed) till it meets the ordinate through B, 

 which represents the limit of solubility in that phase. It 

 leaves the limit of solubility CF, in the other phase, at F, 



Fig. 4. 



'CONCENTRATION 



/00% SOLUTE 



where CF = BE (see paragraph (8)), and probably remaining 

 concave upwards, it touches the ordinate through D at 

 infinity. 



(12) This last proposition is provable thus : — In this 

 Magazine, series 6, vol. xvii. 1909, p. 604, Dr. Burton and 

 I have established the following exact relations, 



&c 2 





and 



3P, 

 dc 2 



»P, 



Ui tS( 



