316 



The expansi ons @.ven by Eqs. (17) are then introduced into Eqs, 

 (12), (13), (14), and (15). A method of successive approximation can be 

 obtained if the coefficient of each power of oC is set equal to zero. The 

 method thus obtained goes as follows. 



(a) First approximation . — The first approximation is 



|r('5:";-5.'".o, (18) 



(.s:'T-(.s':T-srsr,^, 



> 



In this approidmation the strains are given by 



r 



(19) 



df- Y 9t\ » sr / j>a^ ' (20) 



(21) 



(22) 



8 



