619 



Vertifl 

 Ultdt u 



tIesM calculatad cUJktt 



of dlteoHatitm 27 Ft, 



Utt/ai UiUtiif at centre, leSFPS. 



tiff l^tKsl Hbcilu at emtrt//tm: Skk 



FIG.5, TYPICAL PiNfiiCrSIS . 



