Manchester ]\Iemoirs, Vol. Iviii. (1914), Av. 5. 3 



R 



The further h}'pothesis is 



SIS'=TIT'= U'U' = 1, 



3*0j /cw cv \ 



cv dz / ' 



or 



dycz '* V?j 



8*6., /3« dzv\ 



dxdj'~ \dx dy J' 

 The simplest mode of looking on these relations is to 

 regard them as giving //, v, zv. Thus 



a 



At any rate we have two specifications, one for P, Q,R, 

 on dynamical principles and one for P,'Q,'R' given by 

 Hooke's Law. 



A very great simplicity results from this mode of 

 treatment whatever view may be held in regard to che 

 nomenclature. 



1. The d}-namical equations can be looked upon as 

 solved. 



2. The forms of displacement are found. 



