150 



REPORT — 1898. 



for these two facts, the value of 3893 at 13°-9 is raised to 9'9923 ; thus 

 the curve shown in iig. 3* is obtained, and the apparent change in value 

 is reduced to about "0003 ohms, or three parts in one hundred thousand. 

 On the whole, then, I conclude that 3873 has changed since 1893 by about 



Fig. 4. No. 3874. 



Result of observations on the 10-ohm coils, used by Professors Ayrton and J. V. Jones. 



Observations of 1893, thus • 

 Observations of 1897, thus + 

 The horizontal divisions are 0'1° C. 

 The vertical divisions are '0002 ohms. 



Fig. 3*. No. 3873. Revised. 



9 3SZ0 



9-3aoo 



93B80 



9seeo 



IS 



Observations of 1893, conectei to final value of i 10-ohm standard, shown thus • 

 Observations of 1897, thus + 



this amount, while 3874 has remained stationary in value. The dis- 

 crepancy between this conclusion and that given by Mr. Solomon in 

 Appendix II. depends on the different values employed for the tempera- 

 ture coefficients. 



