GSS Dr. U. I). Kleeman on the Equation of Continuity 



to the base e. Now, E must have the same value at the 

 critical temperature as at lower temperatures. Substituting 

 for E its value 



in the above equation, we have 



4/3 



T c = 1189-6 (J) (2v /^ 3 . 



This relation between T., p c , m } and m u has already been 

 obtained by the writer in a previous investigation *. The 

 numerical coefficient in the equation obtained in the above 

 way is also of the proper magnitude. Thus the value of the 

 coefficient calculated by means of the equation using the 

 critical data of ether is 1127, which is approximately the 

 same as that given above. Equation (12) also leads to the 

 above equation. 



We have seen that each of the left-hand sides of equations 

 (11) and 12 is equal to Lra multiplied by a numerical 

 constant. This gives another formula for the internal heat 

 of evaporation which may be written 



l = k *~'<;< a* 



where K 4 is a numerical constant. If x in the equation 



^W-/'5)+rt«i-«i)-*=o 



is zero, then it follows from the equation from which equa- 

 tion (11) is derived that K 4 is equal to 2. The actual value 

 of K 4 was found to be equal to about 1*75. This is shown 

 by the seventh and fourteenth columns of Table IT., which 

 contain values of K 4 calculated by means of equation (13). 

 It will be seen that K 2 is not quite independent of the tem- 

 perature, it usually increases slightly with the temperature 

 till near the critical point and then decreases again. The 

 constancy of K 4 is further tested in Table V. for several 



* Phil. Mag. Dec. 1909, p. 906 ; (a) pp. 783-78; 



