POL'i'MORPHIC TRANSFORMATIONS OF SOLIDS. 



83 



pressure than with falling. This was found at all temperatures; it 

 may well be that it is not a genuine effect peculiar to the pure sub- 

 stance, but is connected with the separating out of mixed crystals of 

 impurities. 



The experimental results are shown in Figure 13, the computed 



5 6 7 8 9 10 

 Pressure, kgm./cm.^ x 10* 



Potassium Nitrite 



Figure 14. Potassium Nitrite. The computed values of the heat of tran- 

 sition and the change of internal energy. 



TABLE VI. 



Potassium Nitrite. 



