416 



Special Reports 



Table iC Results of Declination Comparisons at the Standardizing Magnetic Observatory of the Department of 

 Terrestrial Magnetism at Washington, 1916 Concluded. 



' All values are referred to station JV m ; N m = E m +0'.7, as derived from this 9eries. Observers: D. O. No. 15, W. F. 

 VVallis of the Department of Terrestrial Magnetism; C. I. W. No. 3, H. W. Fisk of the Department of Terrestrial Magnetism. 

 s These are values obtained with C. I. W. No. 3 referred to I. M. S.; I. M. S C. I. W. No. 3= O'.l. 

 ' This value was obtained from 4 magnet-inverted and 2 magnet-erect readings only. 



Table 4D. Resvlts of Special-Test Declination Comparisons at the Standardizing Magnetic Observatory of the 

 Department of Terrestrial Magnetism at Washington, 1916. 



1 C. I. W. No. 3 was at station ./Vm and D. O. No. 1977 at station Sm throughout; all values are referred to station 

 A'; A r m = S+0'.5, see Table 4A. Observers: D. O. No. 1977, C. A. French of the Dominion Observatory; C. I. W. No. 3, 

 II W. I'isk of the Department of Terrestrial Magnetism. 



These are values obtained with C. I. W. No. 3 referred to I. M. S.; I. M. S C. I. W. No. 3 = O'.l. 



J The vertical displacement between highest-possible and lowest-possible positions of magnet 10 in the magnet-house 

 of D. O. No. 1977 is about 1 mm. only. 



Magnet 10 of D. O. No. 1977 was dropped on floor of Observatory between local mean times 15h 47m and 15h 49m. 



