14 R- F. GWVTHER, Specification of the elonents of stress, 



elemental stress couple would play the main part in the 

 general phenomena of stress and would not have escaped 

 notice. It will, therefore, be supposed that kjii is small, 

 and hence that 



^'f ?/.. _., \_ ^%.. _.. \\ 



ny- 



11 (oi; (Z- J 



- '^vV,, etc (24). 



n 



Finally, we obtain these relations : 



5 -, , 



« = —(/■ + /^/j + /^<, ), etc., where 



Ox 



"^JM ^1^ OJj^ 



- .>+,., + -. .1 = U, 

 r.v rjr fis' 



■■ , k ,. A . 



f'A'i +^ V7<i = U, etc., 



and where 

 and where also 



which represents the type of three equations with the 

 subscript numbers i, 2, or 3, and which includes also the 

 small viscous terms. 



To eliminate /m' requires further differentiation in 

 time, and a type of equation is then obtained which may 

 be the subject of further consideration in the hope of 

 explaining some phenomena, such as elastic after strain. 



8. General case. 



Application of the method to the general case where 

 the stresses are not identical with the ideal elastic 

 stresses. 



In order to develop the proposed method in as simple 

 a form as possible, I have assumed up to the present that 

 S—S\ T—l\ U=U' are completely satisfied, and have 

 proposed that the equality of P and P\ Q and Q', R and 

 R' should be of the nature of a test. 



