Tables 677-^S78. 



TERRESTRIAL MAGNETISM {continued). 



TABLE 577. — Agonic Line. 



433 



The line of no declination appears to be still moving westward in the United States, but, as the line of no annual 

 change is only a short distance to the west of it, it is probable that the extreme westerly position will soon be reached. 



TABLE 578. — Mean Magnetic Character of Each Month in the Years 1906 to 1922.* 



Means derived from daily magnetic characters based upon the following scale: o, no disturbance; 1, moderate 

 disturbance, and 2, large disturbance. 



♦ Compiled from annual reviews of the " Caract^re magn^tique de chaque jour," prepared by the Royal Meteoro- 

 logical Institute ol the Netherlands for the International Commission for Terrestrial Magnetism. 



Smithsonian Tables, 



