218 Dr. J. Prescott on the 



After the usual arithmetic we find that 

 F(» = 21-64, 

 /(»= -0-1974, 

 whence , 21*64 1f o 97v 2W 



" = rl X 60 x 0-1974 = 1827X -Q-' ' { ] 

 and consequently 



t l»i 4 I 4 = 5 + v = 4-482 + 1-827 ~ 



f 2W 1 



= 4-482 < 1 -f 0407 x^ >, 



Jm 2 Z 2 = a/4-482 j 1 + 0*407 ~ [> , 



M* = /4'4«2<1 + 0*407 



or . QP i 



wl 

 QI* 



as 



/ yy \ yy 



Therefore, dividing by ( 1 + 0*407 —J and treating -tt 

 a small traction, \ . vc V 



Wl 



Z 2 CH 1-0-407 jj V =8 V'4'482 \/EnCK } 



or QP-0-407 W/ 3 = 16-94 ^/EMJK, 



whence P/ 2 + ()-593W/ 2 =16 ( J4 v'EnUET 



This result can be written in the form 



P72 W/2 



1«VSW E " UK <" 8 > 



Now when P is zero the present problem reduces to 

 Case 7, the solution of which is 



28-31 



But this differs very little from what we should get by 

 putting P = in (173), which has been obtained on the 

 widely different assumption that W is small compared 

 with P. Then it is very likely that equation (173) is nearly 

 correct for all values of the ratio W : P. 



The constants EC and K?i, which are involved in the 

 buckling loads, occur merely as constants in equations for 

 bending and torsion respectively ; that is, there is no 



_ 



