﻿MANUAL 
  OF 
  FISH-CULTURE. 
  35 
  

  

  WATER 
  FOR 
  A 
  SALMON 
  HATCHERY. 
  

  

  The 
  first 
  requisite 
  for 
  a 
  salmou 
  hatchery 
  is 
  an 
  ample 
  supply 
  of 
  suit- 
  

   able 
  water, 
  on 
  a 
  site 
  where 
  it 
  can 
  be 
  brought 
  completely 
  under 
  control 
  

   and 
  the 
  proper 
  tall 
  secured. 
  In 
  this 
  matter 
  there 
  is 
  quite 
  a 
  range 
  of 
  

   choice. 
  The 
  very 
  best 
  is 
  the 
  water 
  from 
  a 
  stream 
  fed 
  by 
  a 
  clean 
  lake 
  of 
  

   considerable 
  depth, 
  taken 
  a 
  short 
  distance 
  below 
  the 
  outlet 
  of 
  the 
  lake, 
  

   with 
  an 
  intervening 
  rapid. 
  Craig 
  Pond 
  may 
  be 
  taken 
  as 
  an 
  example 
  of 
  

   such 
  a 
  lake. 
  It 
  has 
  an 
  area 
  of 
  1*31 
  acres, 
  an 
  extreme 
  depth 
  of 
  69 
  feet, 
  

   and 
  a 
  depth 
  of 
  25 
  feet 
  within 
  500 
  feet 
  of 
  the 
  outlet. 
  The 
  depth 
  directly 
  

   iniiuences 
  the 
  temperature 
  and, 
  other 
  things 
  being 
  equal, 
  a 
  deep 
  lake 
  

   will 
  afford 
  water 
  more 
  uniform 
  in 
  temperature 
  than 
  a 
  shallow 
  one 
  — 
  cooler 
  

   in 
  summer 
  and 
  warmer, 
  though 
  never 
  too 
  warm, 
  in 
  winter. 
  Such 
  water 
  

   is 
  commonly 
  quite 
  even 
  in 
  volume 
  and 
  temperature, 
  and 
  comparatively 
  

   pure. 
  It 
  is 
  cold 
  in 
  winter 
  and 
  warms 
  up 
  slowly 
  in 
  spring, 
  assuring 
  a 
  

   slow, 
  normal 
  development 
  of 
  the 
  eggs, 
  which 
  is 
  more 
  conducive 
  to 
  

   health 
  and 
  vigor 
  than 
  a 
  quicker 
  development. 
  The 
  passage 
  down 
  a 
  

   rapid 
  will 
  further 
  improve 
  this 
  water 
  by 
  charging 
  it 
  highly 
  with 
  air. 
  

  

  After 
  this, 
  the 
  water 
  of 
  a 
  brook 
  is 
  to 
  be 
  chosen 
  that 
  is 
  fed 
  largely 
  by 
  

   springs, 
  so 
  as 
  to 
  insure 
  constancy 
  in 
  the 
  supply 
  and 
  some 
  moderation 
  

   of 
  the 
  temperature 
  on 
  warm 
  days, 
  but 
  it 
  is 
  better 
  to 
  have 
  the 
  water 
  

   flow 
  a 
  long 
  distance 
  in 
  an 
  open 
  channel 
  before 
  using, 
  and, 
  if 
  possible, 
  

   over 
  a 
  rough 
  and 
  descending 
  bed, 
  that 
  it 
  may 
  be 
  well 
  aerated, 
  and 
  in 
  

   cold 
  weather 
  somewhat 
  cooled 
  down 
  from 
  the 
  temperature 
  with 
  which 
  

   it 
  springs 
  from 
  the 
  ground. 
  

  

  Thirdly, 
  choose 
  pure 
  spring 
  water; 
  but 
  in 
  all 
  cases 
  where 
  this 
  is 
  

   necessary 
  provide 
  a 
  cooling 
  and 
  aerating 
  pond, 
  that 
  the 
  original 
  warmth 
  

   of 
  the 
  water 
  may 
  be 
  subdued 
  by 
  the 
  cold 
  of 
  the 
  air 
  before 
  it 
  reaches 
  

   the 
  hatching-troughs, 
  and 
  that 
  it 
  may 
  absorb 
  more 
  or 
  less 
  air 
  by 
  its 
  

   wide 
  surface. 
  

  

  Lastly, 
  choose 
  ordinary 
  river 
  or 
  brook 
  water, 
  as 
  clean 
  as 
  i^ossible. 
  

   The 
  latter 
  are 
  considered 
  inferior 
  to 
  spring 
  water 
  by 
  reason 
  of 
  their 
  

   liability 
  to 
  floods, 
  drought, 
  muddiness, 
  and 
  foulness 
  of 
  other 
  sorts, 
  and 
  

   in 
  cold 
  climates 
  to 
  anchor 
  ice. 
  Between 
  these 
  different 
  sorts 
  there 
  is 
  

   of 
  course 
  an 
  infinite 
  number 
  of 
  gradations. 
  If 
  lake 
  water 
  can 
  not 
  be 
  

   obtained 
  it 
  would 
  be 
  of 
  so«ue 
  advantage 
  to 
  have 
  a 
  supply 
  of 
  both 
  

   spring 
  water 
  and 
  brook 
  water, 
  depending 
  for 
  ordinary 
  use 
  on 
  the 
  brook 
  

   water 
  or 
  a 
  mixture 
  of 
  the 
  two, 
  and 
  on 
  the 
  spring 
  water 
  for 
  emergencies, 
  

   such 
  as 
  the 
  freezing, 
  drying, 
  or 
  excessive 
  heating 
  of 
  the 
  brook, 
  floods 
  

   with 
  accompanying 
  muddiness, 
  etc. 
  Avoid 
  water 
  coming 
  from 
  boggy 
  

   and 
  stagnant 
  ponds 
  and 
  marshes; 
  for 
  though 
  excellent 
  water, 
  capable 
  

   of 
  bringing 
  out 
  the 
  most 
  vigorous 
  of 
  fish, 
  may 
  sometimes 
  be 
  had 
  in 
  

   such 
  places, 
  yet 
  when 
  not 
  supplied 
  by 
  springs 
  it 
  is 
  dependent 
  for 
  its 
  

   freshness 
  and 
  good 
  qualities 
  upon 
  rainfalls, 
  and 
  if 
  these 
  fail, 
  as 
  they 
  

   are 
  liable 
  to, 
  the 
  water 
  may 
  become 
  foul 
  and 
  unfit. 
  It 
  must 
  be 
  borne 
  

   in 
  mind 
  that 
  these 
  remarks 
  about 
  the 
  selection 
  of 
  water 
  for 
  fish-cultural 
  

   purposes 
  apply 
  only 
  to 
  the 
  culture 
  of 
  Atlantic 
  or 
  landlocked 
  salmon, 
  

   in 
  a 
  climate 
  like 
  that 
  of 
  the 
  State 
  of 
  Maine. 
  

  

  