Melting temperatures were measured and the solid liquid phase diagrams were constructed for 1
8 cineole+trichloromethane and 1
8 cineole+tetrachloromethane It is evident from the phase diagram that 1∶1 congruently melting solid addition compound C 10 H 18 O·HCCl 3 form in (1- x )C 10 H 18 O+ x CHCl 3 (1- x )C 10 H 18 O+ x CCl 4 is a simple eutectic system.