﻿FIGHTING 
  INSECTS 
  WITH 
  AIRPLANES 
  

  

  337 
  

  

  Photograph 
  bj 
  

  

  the 
  poison 
  powder 
  hopper 
  attached 
  to 
  the 
  airplane 
  fuselage 
  

   (see 
  text, 
  page 
  336) 
  

  

  When 
  the 
  aperture 
  at 
  the 
  bottom 
  of 
  the 
  hopper 
  is 
  opened 
  by 
  pulling 
  the 
  looped 
  wire 
  

   handle 
  upward, 
  and 
  the 
  crank 
  above 
  is 
  turned, 
  the 
  sprocket 
  chain 
  revolves 
  a 
  mechanism 
  

   which 
  throws 
  the 
  powder 
  out. 
  Upon 
  its 
  release 
  from 
  the 
  hopper, 
  the 
  powder 
  is 
  seized 
  by 
  

   the 
  "slip 
  stream," 
  the 
  violent 
  current 
  of 
  air 
  from 
  the 
  propeller, 
  and 
  is 
  immediately 
  converted 
  

   into 
  a 
  dense 
  cloud 
  of 
  dust, 
  which 
  floats 
  out 
  behind 
  the 
  plane. 
  

  

  post 
  and 
  pole 
  timber. 
  It 
  was 
  a 
  rectangu- 
  

   lar 
  plot 
  800 
  feet 
  long 
  and 
  325 
  feet 
  wide 
  

   and 
  contained 
  approximately 
  six 
  acres. 
  

   The 
  trees, 
  4,815 
  in 
  number, 
  were 
  from 
  

   25 
  to 
  30 
  feet 
  tall. 
  

  

  The 
  poison 
  was 
  applied 
  between 
  3 
  and 
  

   4 
  o'clock 
  on 
  the 
  afternoon 
  of 
  August 
  3, 
  

   1 
  92 
  1, 
  under 
  almost 
  ideal 
  weather 
  con- 
  

   ditions. 
  The 
  atmosphere 
  and 
  sunlight 
  

   were 
  excellent 
  for 
  photographing 
  and 
  

   there 
  was 
  a 
  steady 
  wind 
  varying 
  from 
  

   eight 
  to 
  eleven 
  miles 
  an 
  hour. 
  The 
  direc- 
  

   tion 
  of 
  the 
  wind 
  is 
  indicated 
  by 
  the 
  arrows 
  

   on 
  the 
  photographs. 
  

  

  EVERY 
  TREE 
  SPRINKLED 
  WITH 
  POISON 
  

  

  The 
  plane 
  flew 
  at 
  a 
  speed 
  of 
  eighty 
  

   miles 
  an 
  hour 
  at 
  an 
  altitude 
  of 
  from 
  20 
  

   to 
  35 
  feet 
  and 
  in 
  a 
  line 
  53 
  yards 
  to 
  the 
  

   windward 
  and 
  parallel 
  to 
  the 
  grove. 
  The 
  

   dense 
  cloud 
  of 
  poison 
  dust 
  thrown 
  out 
  

   behind 
  the 
  moving 
  plane 
  was 
  grasped 
  by 
  

   the 
  wind 
  and 
  floated 
  through 
  and 
  over 
  

   the 
  grove, 
  covering 
  the 
  foliage 
  in 
  its 
  pas- 
  

   sage. 
  

  

  We 
  feared 
  that 
  the 
  dust 
  might 
  all 
  settle 
  

  

  on 
  the 
  trees 
  in 
  the 
  immediate 
  foreground, 
  

   but 
  to 
  our 
  surprise 
  we 
  observed 
  that 
  little 
  

   currents 
  of 
  air 
  which 
  we 
  termed 
  "booster 
  

   currents" 
  were 
  rising 
  in 
  the 
  grove 
  and 
  

   these 
  had 
  a 
  tendency 
  to 
  toss 
  the 
  settling 
  

   dust 
  cloud 
  upward, 
  whereupon 
  it 
  would 
  

   be 
  grasped 
  by 
  the 
  wind 
  blowing 
  parallel 
  

   to 
  the 
  earth's 
  surface 
  and 
  thus 
  carried 
  

   onward, 
  even 
  to 
  and 
  beyond 
  the 
  far 
  side 
  

   of 
  the 
  grove. 
  

  

  Not 
  a 
  tree 
  could 
  be 
  found, 
  and 
  many 
  

   were 
  climbed 
  and 
  examined, 
  whose 
  leaves 
  

   did 
  not 
  bear 
  particles 
  of 
  the 
  deadly 
  poison, 
  

   easily 
  detected 
  by 
  the 
  unaided 
  eye. 
  

  

  In 
  all, 
  the 
  dusting 
  plane 
  passed 
  the 
  grove 
  

   six 
  times 
  and 
  distributed 
  about 
  175 
  pounds 
  

   of 
  the 
  poison. 
  Since 
  each 
  passage 
  re- 
  

   quired 
  but 
  nine 
  seconds, 
  the 
  total 
  time 
  

   consumed 
  in 
  the 
  actual 
  work 
  of 
  dusting- 
  

   was 
  54 
  seconds, 
  thus 
  establishing 
  a 
  

   world's 
  record 
  for 
  speed 
  in 
  applying 
  in- 
  

   secticides 
  to 
  forest 
  areas. 
  

  

  Y\ 
  r 
  ith 
  a 
  dust-liberating 
  apparatus 
  of 
  

   greater 
  capacity 
  it 
  would 
  be 
  possible 
  to 
  

   decrease 
  the 
  number 
  of 
  passages 
  by 
  the 
  

   grove 
  and 
  thus 
  lower 
  still 
  more 
  the 
  time 
  

  

  