£% 



100 



Presentation angle 

 ,o -,50 



30^ 



Fig. 13. — Efficiency of deposition of Lycopodium spores on zones across glass 



microscope slide at presentation angles from (left side of left-hand figure) to 90 



(right side of right-hand figure) degrees as observed in wind-tunnel experiments. 



F% = efficiency as percentage area dose; A, B, C, D, E = successive half-centimetre 



