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  together, 
  the 
  inner 
  side 
  of 
  one 
  sHce 
  being 
  covered 
  with 
  Schweinf 
  urt 
  green 
  

   or 
  arsenic 
  ; 
  in 
  order 
  to 
  keep 
  the 
  slices 
  in 
  position 
  they 
  are 
  fastened 
  

   with 
  wooden 
  pins 
  (matches). 
  These 
  pieces 
  are 
  then 
  buried 
  to 
  a 
  depth 
  

   of 
  about 
  three 
  to 
  four 
  inches, 
  after 
  the 
  beds 
  are 
  quite 
  ready 
  for 
  sowing. 
  

   They 
  attract 
  the 
  larvae, 
  which 
  eat 
  into 
  the 
  poisoned 
  slices 
  and 
  perish. 
  

  

  RoLET 
  (A.). 
  Disinfection 
  des 
  sols 
  par 
  le 
  sulfure 
  de 
  carbone. 
  [Soil 
  

   disinfection 
  with 
  carbon 
  bisulphide.] 
  — 
  Journ. 
  Agric. 
  jpratique^ 
  

   Paris, 
  xxvii, 
  no. 
  3, 
  15th 
  Jan. 
  1914, 
  pp. 
  89-91. 
  

  

  The 
  use 
  of 
  carbon 
  bisulphide 
  for 
  the 
  disinfection 
  of 
  soils 
  is 
  being 
  more 
  

   and 
  more 
  widely 
  counselled. 
  In 
  certain 
  cases 
  176 
  lb. 
  of 
  carbon 
  

   bisulphide 
  may 
  be 
  quite 
  sufficient 
  for 
  an 
  acre, 
  but 
  as 
  much 
  as 
  3,344 
  lb. 
  

   has 
  been 
  used. 
  One 
  ton 
  per 
  acre 
  will 
  not 
  injure 
  flowers 
  or 
  vegetables, 
  

   but 
  expense 
  is 
  a 
  consideration. 
  Light 
  soils 
  are 
  most 
  suited 
  for 
  this 
  

   method, 
  as 
  in 
  them 
  the 
  fumes 
  spread 
  easily 
  and 
  rapidly, 
  and 
  less 
  

   bisulphide 
  is 
  required, 
  1 
  oz. 
  at 
  a 
  depth 
  of 
  4 
  inches 
  being 
  sufficient 
  for 
  

   a 
  square 
  yard, 
  while 
  in 
  a 
  compact 
  soil 
  IJ 
  oz. 
  is 
  necessary. 
  In 
  soils 
  

   that 
  are 
  too 
  compact 
  or 
  too 
  damp, 
  the 
  chemical 
  is 
  localised 
  too 
  long, 
  

   and 
  may 
  thus 
  burn 
  plant 
  roots 
  and 
  finally 
  disperse 
  without 
  reaching 
  

   the 
  noxious 
  organisms. 
  The 
  holes 
  made 
  in 
  such 
  soils 
  should 
  be 
  pre- 
  

   pared 
  for 
  the 
  bisulphide 
  by 
  a 
  special 
  boring 
  nozzle 
  fitted 
  on 
  the 
  injector, 
  

   more 
  of 
  the 
  chemical 
  being 
  required 
  the 
  deeper 
  the 
  holes. 
  The 
  depth 
  

   should 
  be 
  a 
  little 
  greater 
  than 
  that 
  at 
  which 
  the 
  pest 
  is 
  found, 
  whenever 
  

   it 
  is 
  possible 
  to 
  locate 
  it. 
  In 
  light, 
  permeable, 
  sandy 
  soils 
  193 
  lb. 
  per 
  

   acre 
  has 
  been 
  used 
  ; 
  in 
  alluvial 
  soil, 
  20 
  to 
  24 
  inches 
  deep, 
  264 
  lb. 
  per 
  

   acre 
  ; 
  in 
  gravel 
  and 
  stony 
  soil, 
  12 
  to 
  14 
  inches 
  deep, 
  an 
  average 
  of 
  193 
  lb. 
  

   per 
  acre. 
  Against 
  Phijlloxera 
  half 
  oz. 
  to 
  about 
  2 
  oz. 
  per 
  square 
  

   yard 
  have 
  been 
  used 
  ; 
  against 
  rot 
  (pourridie) 
  about 
  7 
  oz. 
  per 
  square 
  

   yard, 
  according 
  to 
  Dufour, 
  and 
  about 
  2J 
  oz. 
  according 
  to 
  Foex. 
  In 
  

   Germany 
  and 
  Holland 
  good 
  results 
  have 
  been 
  attained 
  against 
  the 
  

   nematodes 
  of 
  the 
  beet 
  with 
  6 
  oz. 
  per 
  square 
  yard 
  ; 
  but 
  in 
  France 
  

   10 
  oz. 
  and 
  more 
  have 
  been 
  recommended. 
  Against 
  white 
  grubs 
  7 
  oz. 
  

   per 
  square 
  yard 
  are 
  used. 
  Only 
  the 
  cultivation 
  of 
  flowers 
  and 
  early 
  

   vegetables 
  can 
  stand 
  the 
  high 
  cost 
  of 
  the 
  large 
  doses 
  to 
  which 
  practice 
  

   appears 
  to 
  be 
  tending. 
  Thus, 
  7 
  to 
  8 
  oz. 
  may 
  be 
  injected 
  when 
  dealing 
  

   with 
  mole 
  crickets 
  injuring 
  cuttings 
  of 
  carnations 
  in 
  boxes. 
  Twenty- 
  

   five 
  holes 
  per 
  square 
  yard, 
  each 
  taking 
  about 
  one- 
  third 
  oz. 
  are 
  required 
  

   in 
  this 
  case, 
  which 
  may 
  be 
  considered 
  as 
  a 
  maximum 
  ; 
  for 
  in 
  many 
  

   instances 
  3 
  to 
  4 
  oz. 
  are 
  sufficient. 
  If, 
  as 
  is 
  advisable, 
  the 
  operation 
  is 
  

   repeated 
  at 
  a 
  week's 
  or 
  a 
  fortnight's 
  interval, 
  the 
  8 
  oz. 
  dose 
  may 
  be 
  

   reduced 
  to 
  about 
  6 
  oz. 
  On 
  unplanted 
  soil 
  the 
  application 
  of 
  carbon 
  bisul- 
  

   phide 
  is 
  carried 
  out, 
  either 
  in 
  spring 
  or 
  in 
  autumn, 
  a 
  little 
  before 
  sowing 
  

   or 
  planting. 
  The 
  soil 
  must 
  have 
  settled 
  and 
  must 
  not 
  be 
  too 
  damp, 
  as 
  

   then 
  the 
  development 
  of 
  gas 
  wdll 
  be 
  imperfect, 
  or 
  the 
  water 
  will 
  wash 
  

   the 
  chemical 
  down 
  into 
  the 
  earth 
  where 
  it 
  will 
  be 
  useless. 
  Dry 
  and 
  

   temperate 
  weather 
  is 
  the 
  best 
  ; 
  hot 
  weather 
  hastens 
  the 
  production 
  of 
  

   gas. 
  When 
  dealing 
  with 
  planted 
  areas 
  it 
  is 
  well 
  to 
  wait, 
  if 
  a 
  severe 
  

   frost 
  is 
  expected, 
  as 
  the 
  evaporation 
  of 
  the 
  bisulphide 
  cools 
  the 
  earth. 
  

   It 
  is 
  generally 
  stated 
  that 
  sowing 
  or 
  planting 
  should 
  be 
  done 
  some 
  15 
  

   or 
  20 
  days 
  after 
  treatment 
  and 
  a 
  little 
  nitrate 
  of 
  soda 
  added 
  when 
  the 
  

   young 
  growths 
  are 
  able 
  to 
  profit 
  b}^ 
  it. 
  However, 
  tomato 
  plants 
  do 
  

  

  