256 



of temperature at li are wilboiit importance for our investigation 

 and may be left apart *). 



( uo.--* 



Fig. 2. 



The second point of transition is difTicult to observe in tlie ascending 

 branch on account of its steepness, in the descending branch it 

 appears more clearly at B. Further we observe in the descending 

 branch a strong undercooling to far below 100° and then a sudden 

 development of heat and congelation. The highest tempeiature reached 

 in this process (18°, 5 below the zero-line) is the point wliere a very 

 unstable solid phase congeals, which we shall call phase 11 (phase 1 

 has the melting point at about 118°), and which after a short time 

 spontaneously and under the development of heat passes into another 



Fig. 3. 



1) They have their cause in the fact that the volume of para azoxy-anisoi 

 changes considerably in melting. The internal sidewall of the beaker gets for this 

 reason detached from its contents and can temporarily rise to a higher temperature, 

 so that a drop, dripping from the solid centre, again occasions a sudden falling 

 of the temperature. 



