BRIDGMAN. — THERMODYNAMIC PROPERTIES OF LIQUIDS. 



75 



Tammann ^^, in their recent theories, give values for the volume at 

 infinite pressure. The values are listed in Table XVI for four of the 

 liquids here investigated, and compared with the volumes found 

 experimentally at 12000 kgm. and 20°. The observed value for ether 

 at 12000 kgm. is actually less than the value predicted by either of 



TABLE XVI. 



these theories for an infinite pressure; and for the other liquids the 

 observed value is close to the predicted minimum. This result serves 

 to emphasize more strikingly a point made in the preceding paper 

 on water; namely, that at high pressures a liquid is more compres- 

 sible than we might expect from its behavior at low pressures. 



One line of inquiry is worth mentioning which seemed promising 

 before the experiments were performed. The question, suggested 

 by such properties of the atom as the atomic re-fraction, was this; is 

 it possible at the higher pressures to assign to each atom its own 

 specific volume as a function of the pressure, and so compute the 

 volume of a compound at any pressure from its chemical constitution? 

 But an examination of the changes of volumes of the two isomers, 

 ether and isobutyl alcohol, shows that the supposed relation does not 

 hold. For if we compare the volumes of equal weights, that is the 

 volume occupied by the same number of atoms, we shall find that at 

 atmospheric pressure the ratio of the volume of ether to that of 

 isobutyl alcohol is 1.102, and that at 12000 kgm. it has dropped to 

 1.038. If the above relation were true, this ratio would be unity. 



58 Tammann, 1. c, see also Korber. 



