Interpretation of Results 
Quarter Power Points of the Function FF(x, y, ft) 
For fixed x in the yt plane: 
_ Ow 4 2px 
1= 2 +o cos 0, 
__ Dw , 2px 
2 *gcosG, 
For fixed t in the xy plane: 
W. 
Wiy= cos G5 
W 
na =— cos As 
_ gcos 8, (3+ t) 
X= Diy 
gcos 6,(St +t) 
an 
PLATE XXxV 
— Olle 
(8.63) 
(8.64) 
(8.65) 
(8.66) 
(8.67) 
(8.68) 
(8.69) 
(8.70) 
