30 ART. 12. — H. HIHOBE : ON THE FUSION SURFACES OF THE 



in this way. If we express the heat capacity of the system by 

 H, and the molecular heat of fusion of naphthalene and phenol 

 by Qn and (2p respectively, then the quantity of phenol crystalis- 

 ed out is : 



V—JP 

 and r= ^ ^^ 



p- JF+ a ' 



The composition of the eutcctic point is to be found in the 

 diagram of Plate II at the intersection of the projection of the 

 fusion curve so displaced and the isothermal curve of the fusion 

 surface of plienol for tlie temperature L As both these curves 

 are straight lines the composition is found readily by this graphical 

 method. 



Quite the same method of calculation applies to the cases 

 in which the fusion curves of phenol were followed up, where 



and ^ = 



N-JN+C 

 On following up the fusion curves of 2)henol were observed, 



On following up the fusion curves of naphthalene, 



