( 1«2 ) 



470/0 * = 0.15 



pressure: norm. 60 90 1'20 atm. 



temp. of compl. mixt. : ()4.8 65.] 65.3 65.3 



49 7o *-=:0.16 



pressure: norm. 30 60 90 120 150 180 atm. 



temp. of compl. mixt. : 65 65 65.1 65.2 65.3 65.5 65.6 



55 7o ■-'^ = 0.18 



pressure: norm. 30 60 90 atm. 



temp. of compl. mixt. : 61.2 61.2 61.3 61.3 



(The percentage of phenol has been given hero. In tlie theory 

 of the surface ip we suppose that the quantity of one of the liquids 

 is J/i(l— .() and of the otlaer M^x^ in which My and Ah represent 

 the molecular weights. Here J/g = Ce H5 OH.) 



These observations prove, that increase of pressure causes the 

 temperature to rise. Considered in connection with the theory of the 

 surface (//, they show that the longitudinal plait (second plait) has a 

 plait-point on the side of the greater volumes and that at that plait- 

 point it turns its hollow side towards the .*-axis. As moreover, it is 

 possible to prove in general theoretically, that rise of temperature 

 makes the plait move in such a way that the projection of the 

 connodal line on the XV plane falls within that of a preceding 

 connodal line, it follows from this, that the longitudinal plaits 

 (second plaits) will be moved to the side of the «-axis if the tem- 

 perature rises. At a certain tempei'ature the two connodal lines 

 will intersect. Then we have three co-existing phases. When the 

 temperature rises, the two points of intersection approach each other, 

 in other words, the phases begin to resemble each other more and 

 more. At last the two curves touch ; there is only one liquid phase 

 left, co-existing with the gas-phase. This temperature is called the 

 temperature of complete mixture. This, however, is but one of the 

 many critical temperatures of complete mixture, for at a higher tem- 

 perature it is possible, by increasing the pressure, to get two liquid 

 phases, which can become perfectly equal in composition and mole- 

 cular volume. In this case also, there is a critical temperature. 

 So the critical tenqjeiatuj-e rises through increase of pressure in 

 the mixture examined. 



