THE RIGIDITY OF THE EARTH 6oi 



the water tides in the N-S direction of +2°4i' and in the E-W 

 direction +4*3 4'. Although it seems certain that the difference in 

 phase is slightly larger in the E-W than in the N-S direction, a 

 mean displacement of +4?o is probably correct to within 1°. If 

 we take 22 = 0.690, the tides in the actual earth are 0.310 of what 

 they would be if the earth were fluid, and the value of A^ equal to 

 4?o, for the displacement of the water tides means that the earth 

 tides lag behind the impressed forces by this same amount. 



It is desired to express appreciation of the interest taken in this 

 work by Professor T, C. Chamberlin, Professor E. B. Frost, and 

 Professor F. R. Moulton. 



Ryerson Laboratory 

 November 1919 



