ATMOSPHERIC PRESSURE BETWEEN 104 C. AND 115 C. 



435 



With any definite calorimetric arrangement the values of S c and k are constant 

 within the limits of experimental error, while h increases linearly with D, fig. 10. 

 In the set of experiments made with the non- vacuum jacket the values of h and k 

 calculated in the manner described on p. 419 are given in the table in brackets. The 

 most probable value of k, viz., 0'00520, has been used in the determination of H in 

 the abridged tables, h being slightly altered in the case of the experiments with 

 D = 11 '5 cm. In the experiments made with the silica calorimeter, with as 

 perfect a vacuum as possible in the jacket, the values of k calculated from the 



09 



5 10 D.cms. 15 



Fig. 10. 



X Prof. CALLENDAR'S experimental values. Unsilvered calorimeters. 

 ,, ,, Silvered 



G> BRIXKWORTH. Mean values. 



individual measurements varied between O'OOOl and 0'0007, and in the calculation 

 of H/Q for these observations the mean value '00030 has been given to k. 



From the observations of May 1st, 1914, it can be seen that the difference in the 

 values of the specific heats as calculated (l) from the experimental values of h and k, 

 and (2) from the adjusted value of h corresponding to k = O'OOOSO, is only 0'05 per 

 cent. In the last column of the above table are given the values of the ratio h per 

 cm/k. Within the limits of error this ratio may be considered constant, and 



