230 



Mr. William Sutherland on the 



For the proper appreciation of this table it must be borue 

 in mind that as soon as we enter the liquid region the pv term 

 of the characteristic equation becomes the small difference of 

 two terms, a small percentage error in either of which becomes 

 a large one in^?v. The fact that the above table brings out 

 is that from 150° to 195° the relation between volume and 

 temperature given by the equation is so accurate as to make 

 only the small errors in pressure in the above table. But to 

 show this more directly, we will now compare the volumes of 

 the liquid under a pressure of 9 metres of mercury between 

 0° and 100°, as determined by Grimaldi (Wied. Beibl. x.) and 

 as given by the equation. The specific gravity of ethyl oxide 

 at 0° and under one atmosphere is taken as '7366. 



Table XVI. (p = 19'5 metre.; 





0°. 



50°. 



100°. 



150°. 





Volume, experiment 



1-355 

 1-354 



1-469 

 1467 



1630 

 1633 



1-9 

 1-9 



,, calculated 





This, taken in conjunction with Table XV., shows that the 

 equation represents with a high degree of accuracy the ex- 

 pansion of liquid ethyl oxide right up to the critical volume. 

 It is now to be tested as to its power to give compressibilities 

 correctly. The next Table contains the calculated compressi- 

 bilities of liquid ethyl oxide, and also the experimental as 

 given by Amagat (Ann. de Chim. et de Pliys. 5 ser. t. xi.), 

 Avenarius (Wied. Beibl. ii.), and Grimaldi (Wied. Beibl. x.). 

 Amagat's values had to be interpolated for comparison with 

 the others. 



Table XVII. 

 Compressibilities with metre of mercury as pressure-unit. 



Temperature 0°. 



40°. 



60°. 



100°. 



Amagat 000200 



Avenarius ; "000178 



Grimaldi ' -000207 



•000309 

 •000317 

 •000316 

 •000300 



•000380 

 000403 

 •000407 

 •000392 



•000730 

 •000654 

 •000632 

 •000710 



Equation -000183 



