BRIDGMAN. 



WATER UNDER PRESSURE. 



523 



that is, the difference of compressibility between solid and liquid. 

 This may evidently be found from the difference of slope above and 

 below the melting point of the curves connecting piston displacement 

 with pressure. If everything had been ideally perfect the other appa- 

 ratus should have given it too, but the quantity to be determined is 



I .OiioU 

 h .0100 



^ 4 



DO 



«o .0^30 

 to 5 

 U 



q: 



a. .0^80 



1 



y .0,G0 



z * 



u 



Pi .0.50 



O ,0^40 



10 20° 30° 40° 50° eO° 

 TEMPERATURE. 



Figure 35. Showing the directly determined values for the difference of 

 compressibility between VI and the liquid at various equihbrium temperatures. 



very small, and the irregularities introduced by the transmitting liquid 

 passing from one vessel to another at a different temperature, which 

 might not be perfectly constant, were so great as not to admit of any 

 results of value. With the high-pressure cylinder, everything is in one 

 piece, and there are fewer complications. The values obtained even 

 with this are very irregular, but they are given as having some value 

 in pointing out the direction of the effect at high pressures. The 

 points are shown with sufficient accuracy in Figure 35. This shows a 

 very rapid decrease in the difference of compressibility at high temper- 

 atures and pressures. 



This completes the presentation of the actual data. The points 

 were determined separately, those on one equilibrium curve being inde- 

 pendent of those on another. But the curves drawn through the 

 points, particularly those for the latent heat and the change of volume, 

 have not been in all cases the best curves through the points of the 



