78 



Mr. J. Rose-Innes on the 



Volume. 



T. 



851-9 

 8354 

 820-8 

 825-6 

 9696 

 935-6 

 846-7 

 787-0 

 808-9 

 8041 

 793-8 

 773-4 

 854-7 

 876-2 

 871-6 

 853-1 

 816-2 

 832-8 

 820-0 

 833-7 

 835-1 

 846-7 

 848-0 



Volume. 



t. i Volume. 



T. 



350 

 300 

 260 



230 



200 



180 



160 



140 , 



120 



100 



90 ... 



80 



70 



60 



50 



45 



40 



36 .. 



33 



30 



28 



26 



24 



22 

 20 

 19 

 18 

 17 

 16 

 15 

 14 

 13 

 12 



11 



10 



9-5... 



9 



8-5... 

 8 



7-5 .. 

 7 , . 

 6-5... 

 6 



5*5 ... 

 5 

 4-6... 



835-8 

 845-9 



854 7 

 848-7 

 850-9 

 845-3 

 854-1 

 848-9 

 847-8 

 844-1 

 840-1 

 843-5 

 846-7 

 838-3 

 834-5 

 833-7 

 833-2 

 8322 

 828-1 

 827-2 

 819-8 

 813-7 

 809-5 



1 



4-3 ... 

 4-0 ... 

 3-8 ... 

 3-6 ... 

 3-4 ... 

 32 ... 

 3-0 ... 

 2-9 ... 

 2-8 ... 

 2-7 ... 

 2 6 ... 

 2-5 ... 

 2-4 ... 

 2-3 ... 

 2-2 



2i ::: 



20 ... 

 1-9 ... 



1-8 ... 

 1-7 ... 

 1-6 ... 



804-6 

 7991 

 792 3 

 777-3 

 7640 

 737-2 

 715-5 

 696-5 

 675-9 

 656-4 

 637-7 

 615-2 

 593-7 

 565-9 

 541-1 

 511-2 

 478-7 

 446-3 

 408-6 

 3672 

 318-4 



Young's paper on ether (Phil. Mag. xxiii. p. 441). Prof. 

 Young has not given any smoothed values of b for isopentane, 

 however, and I have thought it better not to use my own. 

 smoothed values, so as to employ numbers that are above the 

 suspicion of bias towards any particular theory. 



The mean value of t for all volumes above 8 is 842*4 ; 

 and this number could be taken as the true value for all such 

 volumes without introducing any serious error. Below vol. 8, 

 however, the value of t distinctly diminishes with the volume ; 

 and by the time the critical point is reached, t is not more 

 than about 801. It is not easy to find a formula for t which 

 will give the experimental results throughout the whole range 

 of volume ; but whatever may turn out to be its proper 

 algebraic expression, there appears to be little doubt that its 

 initial decrease from the maximum value varies as a higher 

 power of the density than the first. 



The result appears to me to be of importance, since it is by 

 itself sufficient to reveal the inadequacy for isopentane of 

 many of the gas-formula? that have been proposed. We have 

 seen that 



av 



bv-R 



Suppose that we can put 



