196 



Messrs. J. P. Kuenen and W. G. Robson on 



teristic blue colour which always precedes critical phenomena, 

 suddenly separates into two liquids. Below 31 0, 9 C, there- 

 fore, the points a and b do not exist : at the moment of their 



Table VI. — Ethane and more Ethyl Alcohol (II.). 



t. 



P- 





3265 

 32-75 

 3295 

 40-75 



C. 47-12 

 47-16 

 47-30 



C. 54-68 



Three phases. 



appearance a small plait is formed, the plait-point of which, 

 so to speak, lies between a and b, which are still close 

 together. With rise of temperature this liquid plait becomes 

 broader and longer, a and b receding from each other. The 

 other plait-point has now (at 32°"16, the critical temperature 

 of ethane) also made its appearance, and gradually approaches 

 the three-phase triangle. The pressures will be seen to be 

 related to each other as in the case of methyl alcohol and 



Table VII.— Ethane and still more Ethyl Alcohol (III.). 



t. 



Pb- 





14-95 



32-81 

 P- 



Two phases. 



32-75 



0. 47-04 



Three phases. 



32-95 



47-26 



j) 



ethane. For instance, at 14°"95 (Table VII.) the two-phase 

 pressure of 32 0, 81 is less than the pressure in Table V. for a 

 mixture containing less alcohol. 



At 35° C, say, the v-x diagram has the appearance shown 

 in fig. 7. No difficulty will be found in imagining the gradual 

 diminution of the plait Pi with further rise of temperature 

 and its disappearance at 40 o, 7. [The two critical points 

 31°*9 and 40 o, 67 are somewhat different from those obtained 

 with more alcohol in the mixtures Tables VI. and VII., a 

 difference due probably to the introduction of impurity.] 



