Comparisons of Magnetic Standards, 1915-21 



399 



Table IB.- 



-Results of Horizontal-Intensity Comparisons at the Standardizing Magnetic Observatory of the Department 

 of Terrestrial Magnetism, at Washington, 1915. 



i All values are referred to station S m ; S m = E m 4.Sy, as derived from this series. Observers: M. S. No. 15, W. E. W. 

 Jackson of the Meteorological Service; C. I. W. No. 3, H. W. Fisk of the Department of Terrestrial Magnetism. 



* These are the values obtained with C. I. W. No. 3, using constants of December 12, 1910, referred to I.M. S.; I. M. S. 

 C. I. W. No. 3 = 0.00000/7. 



' Constants of April 14, 1910, were used in obtaining these values. 



Table 1C- 



-Resnlis of Inclination Comparisons at the Standardizing Magnetic Observatory of the Department of 

 Terrestrial Magnetism at Washington, 1915. 



' All values are referred to station S,; S. = jBm+0'.0, as derived from this series. Observers: M. S. No. 89, W. E. W. 

 Jackson of the Meteorological Service; C. I. W. No. 48, H. W. Fisk of the Department of Terrestrial Magnetism. 



These are values obtained with C. I. W. No. 48; I. M. S. C. I. W. No. 4S = 0'.0. 



' A magnetic storm was in progress during these observations; extreme precautions were taken to make the observa- 

 tions with the 2 instruments strictly simultaneous. 



Comparisons at Agincourt, 1916. 



Declination and horizontal-intensity comparisons with Agincourt standards were 

 secured by the Observatory staff in April 1916 through observations with the Meteor- 

 ological-Service magnetometer C.I.W. No. 15 after its return from Washington. 

 Director R. F. Stupart has courteously communicated the results of the comparisons 

 as shown by Tables 1 D and 1 E and accompanying foot-notes, thus making it possible 

 to obtain once again relations between the Agincourt standards and I. M.S. The 

 Director of the Meteorological Service stated, when communicating these data, that 

 beginning with January 1916 all Agincourt values in declination would be referred to 

 pier E and corrected on I. M.S. by the means of the relations deduced from the com- 

 parisons at Agincourt during April 1916 in declination and horizontal intensity; he 

 stated also that inclinations obtained through the Toepfer inductor No. 89 would be 

 corrected on I. M.S. by the relation as determined by the Washington comparisons of 



