Comparisons of Mercury and Platinum Thermometers. 45 



Old. Corrected. 



A , . -o ("Rowland (air-scale) . . . 4-189 x 10 7 4' 187 x 10 7 

 At I0 \Grimths(N. scale) ... 4-198 „ 4-190 „ 



f Rowland 4-179 „ 4-181 „ 



At 2QO I Griffiths 4-192 „ 4-184 „ 



| Schuster and Gannon 



L (N. scale) at 19°-1.. 4-1905 „ 4-185 „ 



., a- f Rowland 4-173 „ 4-176 „ 



At '° \ Griffiths 4-187 „ 4-179 ,. 



Dr. Gnthe has kindly informed me of the result of a 

 redetermination of the electrochemical equivalent of silver, 

 which was carried out during the past year by Professor 

 Patterson* and himself at the University of Michigan. Their 

 final value of the electrochemical equivalent of silver is 

 0-0011193 gramme per ampere per second for a "used" 

 solution. This is very near the value found by Kahle for 

 a used solution. For a " fresh " solution Kahle found 

 0-0011182. 



A recalculation of the E.M.F. of the Cambridge standard 

 Clark cell as determined by Glazebrook and Skinner, if we 

 use the value of the equivalent found by Guthe and 

 Patterson, is 



Cambridge 15 ° = 1*4327 volts, 



which is in very close agreement with the value as given by 

 Kahle. If Griffiths' values are corrected in accordance with 

 this determination, the agreement with Rowland's corrected 

 values is very close, they being greater by about 1 part in 

 2300 throughout the range 15° to 25°. 



In conclusion the authors wish to express their sincere 

 appreciation of Professor Rowland's kindness in allowing the 

 use of his thermometers for these comparisons, and their many 

 obligations to Professor Rowland and Professor Ames for 

 their frequent advice and assistance throughout the course of 

 this work ; and also to Dr. W. S. Day for so freely placing 

 his apparatus at our disposal, and his many acts of kindness. 



Johns Hopkins University, 



Baltimore. 



* The results of this investigation have since heen published in the 

 Phys. Rev., Dec. 1898, p. 257. 



