978 
Temperature Observed pressure Calculated pressure 
308.5 0.07 atm. 0.03 atm. 
346 gas | Oni. 
379.5 0.35 , 0.33 , 
408.5 ord, Ds, 
433.5 a 1.52 , 
450.5 2.30. 5 2.34: , 
463.5 3.18 , 3.22 , 
472.5 3.88 , 3.99 , 
486.5 5.46, 5.51 , 
505 8.61 , 8.29 , 
515 10.43, 10.26 , 
522.5 11.61 , 11.98 , 
561 (24.2) 5.5» 
578 34.35 , 34.95 , 
581 36.49 , 36.90 , 
587.5 ATT , 41.38 „ 
588 42.10 , Aas 
589 42.6 , 45 
589.5 43.1 , Eda 
2. Heat of sublimation, heat of evaporation and heat of melting 
of the violet phosphorus in connection with the theory of allotropy. 
From the foregoing calculations exceedingly remarkable conclusions 
may be drawn. 
) 
From the value for © = 13050 follows for the mol. heat of subli- 
mation the extraordinarily high value 25.839 K. Cal., while we 
have found 9.962 K. Cal. for the mol. heat of evaporation of liquid 
violet phosphorus, so that 15.877 K. Cal. follows from these two 
quantities for the mol. heat of melting. 
According to the theory of allotropy evaporation and melting is 
accompanied with a chemical reaction between the pseudo components 
of the substance, and the more the coexisting phases differ in con- 
