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  devised 
  that 
  they 
  will 
  be 
  soluble 
  in 
  ammonia. 
  The 
  test 
  will 
  not 
  indicate 
  

   the 
  presence 
  of 
  soluble 
  arsenic 
  or 
  of 
  arsenic 
  trioxide, 
  and 
  if 
  unusually- 
  

   severe 
  burning 
  occurs, 
  or 
  if 
  suspicion 
  of 
  adulterants 
  is 
  aroused 
  by 
  

   means 
  of 
  the 
  test 
  just 
  explained, 
  a 
  sample 
  should 
  be 
  submitted 
  to 
  a 
  

   competent 
  chemist 
  for 
  analysis. 
  For 
  use 
  dry, 
  the 
  Paris 
  green 
  should 
  

   be 
  mixed 
  with 
  20 
  times 
  its 
  weight 
  of 
  flour 
  or 
  air-slaked 
  lime, 
  well 
  sifted 
  

   and 
  dusted 
  on 
  to 
  the 
  plants, 
  preferably 
  after 
  rain 
  or 
  when 
  they 
  are 
  

   wet 
  with 
  dew. 
  As 
  a 
  spray 
  the 
  following 
  are 
  advised 
  : 
  — 
  For 
  potato 
  

   beetles 
  (Leptinotarsa 
  10-lineata), 
  1 
  oz. 
  of 
  green 
  in 
  4 
  gals, 
  of 
  water 
  ; 
  

   for 
  cabbage 
  worms, 
  1 
  oz. 
  with 
  4 
  oz. 
  of 
  soap 
  in 
  4 
  gals, 
  of 
  water 
  ; 
  for 
  

   sugar-beet 
  webworm 
  {Phlyctaenodes 
  sticticalis), 
  2 
  oz. 
  with 
  4 
  oz. 
  of 
  soap 
  

   in 
  4 
  gals, 
  of 
  water 
  ; 
  for 
  cutworms, 
  8 
  oz. 
  with 
  20 
  lb. 
  of 
  wheat 
  bran, 
  

   1 
  quart 
  of 
  cheap 
  molasses, 
  and 
  water 
  enough 
  to 
  render 
  the 
  mixture 
  

   wet 
  but 
  not 
  sloppy 
  ; 
  a 
  small 
  quantity 
  of 
  this 
  bait 
  to 
  be 
  placed 
  on 
  the 
  

   base 
  of 
  plants 
  to 
  be 
  protected 
  late 
  in 
  the 
  afternoon 
  or 
  in 
  the 
  evening. 
  

   In 
  the 
  use 
  of 
  all 
  sprays 
  containing 
  Paris 
  green 
  care 
  must 
  be 
  taken 
  that 
  

   the 
  mixture 
  is 
  thoroughly 
  agitated 
  during 
  use, 
  or 
  uniform 
  distribution 
  

   will 
  not 
  be 
  obtained. 
  Paris 
  green 
  is 
  not 
  recommended 
  for 
  fruit 
  trees 
  

   because 
  of 
  its 
  liability 
  to 
  injure 
  the 
  foliage. 
  It 
  is 
  easy 
  to 
  apply 
  and 
  

   acts 
  quickly, 
  but 
  at 
  the 
  same 
  time 
  is 
  easily 
  washed 
  off 
  by 
  rain. 
  The 
  

   local 
  price 
  is 
  given 
  at 
  Is. 
  O^d. 
  per 
  lb. 
  wholesale 
  and 
  Is. 
  6^d. 
  per 
  lb. 
  

   retail. 
  

  

  Arsenate 
  of 
  Lead. 
  The 
  State 
  laws 
  require 
  that 
  commercial 
  brands, 
  

   in 
  paste 
  form, 
  must 
  not 
  contain 
  more 
  than 
  50 
  per 
  cent, 
  of 
  water 
  and 
  

   must 
  contain 
  arsenic 
  equivalent 
  to 
  12 
  J 
  per 
  cent, 
  of 
  arsenic 
  oxide 
  ; 
  

   not 
  more 
  than 
  the 
  equivalent 
  of 
  3 
  to 
  4 
  per 
  cent, 
  of 
  arsenic 
  oxide 
  soluble 
  

   in 
  water 
  is 
  permitted. 
  The 
  authors 
  give 
  various 
  catalogue 
  names 
  for 
  

   lead 
  arsenate 
  and 
  say 
  that 
  there 
  are 
  practically 
  only 
  two 
  kinds 
  which 
  

   are 
  of 
  value. 
  One, 
  ortho 
  or 
  neutral 
  arsenate 
  of 
  lead, 
  having 
  the 
  for- 
  

   mula 
  Pb.3 
  (As0.])2, 
  and 
  acid 
  arsenate 
  of 
  lead, 
  which 
  has 
  the 
  formula 
  

   PbHAsOi. 
  According 
  to 
  law, 
  the 
  first 
  of 
  these 
  preparations 
  should 
  

   contain 
  25 
  per 
  cent, 
  of 
  arsenic 
  oxide 
  on 
  a 
  dry 
  basis 
  and 
  the 
  latter 
  

   33 
  per 
  cent. 
  Many 
  of 
  the 
  preparations 
  sold 
  commercially 
  are 
  mixtures 
  

   of 
  the 
  two, 
  but 
  the 
  authors 
  strongly 
  recommend 
  the 
  acid 
  arsenate 
  

   because 
  of 
  the 
  higher 
  arsenic 
  content 
  and 
  the 
  fact 
  that 
  it 
  does 
  not 
  

   settle 
  so 
  rapidly 
  when 
  mixed 
  with 
  water. 
  They 
  do 
  not 
  advise 
  even 
  

   large 
  growers 
  to 
  make 
  their 
  own 
  arsenate 
  from 
  acetate 
  of 
  lead 
  and 
  

   arsenate 
  of 
  soda. 
  They 
  give 
  the 
  following 
  formulae 
  for 
  use 
  : 
  — 
  Against 
  

   codling 
  moth 
  {Cydia 
  pomonella), 
  2 
  lb. 
  in 
  50 
  gals, 
  of 
  water 
  ; 
  against 
  

   green 
  fruit 
  worm 
  and 
  tussock 
  moth 
  caterpillars 
  {Hemerocampa), 
  5 
  oz. 
  

   in 
  4 
  gals, 
  of 
  water 
  ; 
  and 
  against 
  all 
  chewing 
  insects 
  4 
  oz. 
  in 
  4 
  gals. 
  

   These 
  formulae 
  are 
  for 
  the 
  paste 
  form 
  ; 
  with 
  dry 
  or 
  powdered 
  arsenate 
  

   of 
  lead 
  use 
  one-half 
  as 
  much. 
  Directions 
  are 
  given 
  for 
  preparing 
  

   a 
  stock 
  mixture 
  and 
  the 
  use 
  of 
  soap 
  is 
  said 
  to 
  be 
  of 
  somewhat 
  question- 
  

   able 
  advantage, 
  as 
  it 
  apparently 
  increases 
  the 
  solubiUty 
  of 
  arsenate 
  

   of 
  lead 
  and 
  thus 
  increases 
  the 
  injury 
  to 
  the 
  foliage. 
  Paste 
  arsenate, 
  if 
  

   stored, 
  should 
  be 
  kept 
  covered 
  with 
  water 
  and 
  precautions 
  taken 
  to 
  

   prevent 
  it 
  freezing. 
  The 
  principal 
  advantages 
  of 
  the 
  dry 
  form 
  are 
  

   that 
  it 
  will 
  keep 
  indefinitely, 
  can 
  be 
  very 
  easily 
  handled, 
  and 
  costs 
  less 
  

   for 
  carriage. 
  With 
  regard 
  to 
  arsenate 
  of 
  lead 
  in 
  combination, 
  mixtures 
  

   should 
  be 
  made 
  only 
  just 
  before 
  use, 
  otherwise 
  chemical 
  changes 
  may 
  

   occur 
  resulting 
  in 
  foliage 
  injury. 
  The 
  disadvantage 
  of 
  arsenate 
  of 
  lead 
  

   is 
  that 
  it 
  acts 
  slowly 
  and 
  that 
  the 
  carriage 
  of 
  the 
  paste 
  forms 
  is 
  

  

  