484 



Prof. A. Schuster. 

 Table II. 



[Mar. 28, 



Observed and calculated Values of the Coefficients t and t 2 when 

 expressed in the form, r x cos (t ^) +r 2 cos 2 (tt 2 ), on the supposi- 

 tion that the disturbing force is o-utside the Earth. 



Table III. 



Observed and calculated Values of i\ and r 2 in the Expression 

 r-L cos (t t-i) +r 2 cos 3 (tt%) for Vertical Force. 



In Table I the comparison of the observed phases is made with the 

 values calculated on the assumption that the disturbing force is 

 inside the earth. In Table II the same comparison is made on the 

 alternative hypothesis. There is complete disagreement in Table I 

 between the observed and calculated values, and nearly complete 

 agreement in Table II. It is seen how both at Lisbon and Bombay 

 the time of maximum displacement agrees within three minutes of 

 time for the diurnal variation, and at Lisbon within four minutes of 

 time also for the semi-diurnal variation. Considering that Lisbon is 

 the most important station, not only on account of its geographical 

 position, but also because the observed vertical forces apply to the 



