41G 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



closer to the upper comer of the curve, as Avill be shown in the magni- 

 fied diagram later, but the lower corner cannot be approached very 

 much more closely, because of the subcooling of the liquid mercury. 



The data are collected in Table X. and shown in Figure 20. These 

 data can be subjected to a calculation exactly like that used for the 

 equilibrium points found by the change of resistance method. A 



TABLE X. 



Freezing Pressure of Mercury at Different Temperatures by the 

 Method of Change of Volume. 



straight line was passed through the midst of the points, the deviations 

 from this line plotted on a large scale, and the best smooth curve drawn 

 through the deviations. The calculated values were obtained from 

 this smooth deviation curve and the original straight line. The points 

 are not so regular here as for the determination by the change of 

 resistance method, and the best smooth curve is open to greater ques- 

 tion. The deviations from linearity are nearly twice that found by the 

 resistance method, namely 140 against 60 kgm. at 12,000. This has 



