585 
In the meanwhile it had been pointed out by Prof. Smits that the 
theory of the allotropy leads us to expect that the previous history 
Figs. Fig. 2. 
might exert an influenee on the situation of the transition point. 
Specially conducted experiments confirmed this surmise completely 
(A. Smits and H. L. pr Leeuw, On the system sulphur, Proc. 1911). 
The 7'— was determined according to Rricner’s method with this 
modification that the upper end of the dilatometer was not sealed. 
The transition temperature was consequently determined at 1 atm. 
pressure, whereas with Rerrcupr the pressure amounted to 4 atm. 
The influence which the pressure exerts on the transition temperature 
is calculated by Retcuer to be equal to */,,° rise per atm. pressure 
increase. This tallies, as instead of 95°.6 observed by Rricnrr, I 
found 95°.45. 
Now in order to find 7’— when S, was present the sulphur was 
heated to boiling in the dilatometer and then rapidly cooled so that 
a great part of the S, formed remained intact. Then the dilatometer 
liquid (a mixture of 9 vol. of turpentine and 1 vol. of CS, which 
had been boiled for a long time with sulphur and showed no longer 
an evolution of gas) was added and the transition point determined 
by ascertaining at which temperature one was above and when one 
was below T'—. In the first case the level of the liquid rises at 
a constant temperature (conversion Sr, Sy), in the second case 
it falls (conversion Sy — Spy). 
Here it was shown that already at a much lower temperature than 
