2 GWVTHER, Rate of Propagation of an EartJi-Trcnior. 

 '' = |^.(^+/.+/3-/i), 



w=U,F^n^f,-f,) (I), 



so that the components of the rotations take the form 



^^(/.-/,), etc, 

 and the tangential shearing stresses the form 



The equations of motion are then satisfied, provided that 



{(\ + 2)u) a2 - p^2/^/2|^= constant, 



{ /x A 2 - pdP-jdt'^ } /= constant, 

 and 



i^ p r- 



^J<f^ +/s -/i) + ^{/s +/i -A] + ^,{/i +/2 -/s} = constant (2). 



I shall suppose that the constants in these equations 

 are usually null, and have other than null values only over 

 certain definite areas. For the limited purpose of this 

 paper, it is only contemplated they have other than null 

 values at definite areas near the free surface. It is plain 

 that this introduces potential functions somewhat after 

 the manner of M. Boussinesq's solutions. 



Besides the dynamical solutions with which we are 

 principally dealing, there are also statical solutions which 

 are separate, and may be different in character, and which 

 are communicated or removed instantaneously and not 

 by a finite time-propagation. We may instance M. 

 Boussinesq's first type of simple solution, for which I find 



k + fj. r 



/3 = 



\ + fjL r 



