﻿MANUAL 
  OF 
  FISH-CULTURE. 
  21 
  

  

  the 
  tray 
  at 
  intervals, 
  care 
  being 
  taken 
  not 
  to 
  raise 
  them 
  out 
  of 
  the 
  

   water, 
  as 
  at 
  this 
  tender 
  age 
  a 
  slight 
  pressure 
  against 
  the 
  wire 
  of 
  the 
  

   tray 
  will 
  often 
  produce 
  fatal 
  injuries. 
  On 
  this 
  account 
  too 
  much 
  caution 
  

   can 
  not 
  be 
  exercised 
  in 
  regard 
  to 
  handling 
  them 
  out 
  of 
  water 
  during 
  

   the 
  first 
  stages 
  of 
  the 
  yolk-sac 
  period, 
  for 
  the 
  injuries 
  can 
  not 
  be 
  seen 
  

   at 
  first, 
  and 
  often 
  the 
  death 
  of 
  the 
  fry 
  is 
  the 
  first 
  warning 
  that 
  they 
  

   have 
  been 
  injured. 
  

  

  After 
  the 
  eggs 
  are 
  all 
  hatched 
  and 
  the 
  young 
  fish 
  are 
  safely 
  out 
  of 
  

   the 
  trays 
  and 
  in 
  the 
  bottom 
  of 
  the 
  troughs 
  their 
  dangers 
  are 
  few 
  and 
  

   they 
  require 
  comparatively 
  little 
  care. 
  Almost 
  the 
  only 
  thing 
  to 
  be 
  

   guarded 
  against 
  now 
  is 
  suffocation. 
  Even 
  where 
  there 
  is 
  an 
  abun- 
  

   dance 
  of 
  water 
  and 
  room, 
  with 
  a 
  good 
  circulation, 
  they 
  often 
  crowd 
  

   together 
  in 
  heaps 
  or 
  dig 
  down 
  under 
  one 
  another 
  until 
  some 
  of 
  them 
  die 
  

   from 
  want 
  of 
  running 
  water 
  which 
  is 
  not 
  an 
  inch 
  away 
  from 
  them. 
  The 
  

   best 
  remedy 
  in 
  such 
  a 
  case 
  is 
  to 
  thin 
  them 
  out. 
  

  

  Eight 
  thousand 
  gallons 
  of 
  water 
  an 
  hour 
  is 
  sufiflcient 
  for 
  ten 
  lines 
  of 
  

   troughs 
  64 
  feet 
  in 
  length, 
  containing 
  altogether 
  a 
  little 
  over 
  1,000,000 
  

   young 
  salmons 
  in 
  the 
  yolk-sac 
  stage. 
  This 
  gives 
  in 
  round 
  numbers 
  

   800 
  gallons 
  of 
  water 
  to 
  each 
  100,000 
  fry 
  every 
  hour, 
  or 
  1G§ 
  gallons 
  per 
  

   minute, 
  which 
  is 
  a 
  safe 
  minimum. 
  

  

  When 
  the 
  yolk-sac 
  has 
  become 
  nearly 
  absorbed 
  the 
  fish 
  rise 
  from 
  the 
  

   bottom 
  of 
  the 
  trough, 
  where 
  they 
  have 
  previously 
  remained, 
  and 
  hold 
  

   themselves 
  up 
  in 
  the 
  water. 
  It 
  is 
  now 
  almost 
  time 
  to 
  begin 
  to 
  feed 
  

   them, 
  and 
  they 
  have 
  become 
  comparatively 
  hardy 
  and 
  require 
  very 
  

   little 
  care. 
  

  

  Close 
  attention 
  is 
  required 
  again, 
  however, 
  as 
  soon 
  as 
  they 
  commence 
  

   to 
  feed. 
  They 
  will 
  show 
  when 
  they 
  are 
  ready 
  to 
  feed 
  by 
  darting 
  to 
  one 
  

   side 
  or 
  the 
  other 
  when 
  small 
  particles 
  of 
  food 
  are 
  dropped 
  in 
  the 
  water 
  

   and 
  floated 
  past 
  them. 
  From 
  this 
  time, 
  for 
  several 
  weeks, 
  the 
  necessity 
  

   for 
  care 
  and 
  vigilance 
  never 
  ceases. 
  

  

  The 
  young 
  fish 
  should, 
  for 
  the 
  first 
  few 
  weeks, 
  be 
  fed 
  regularly 
  and 
  

   as 
  often 
  as 
  six 
  times 
  a 
  day, 
  and 
  the 
  earlier 
  in 
  the 
  day 
  the 
  feeding 
  begins 
  

   and 
  the 
  later 
  it 
  continues 
  at 
  night 
  the 
  better. 
  Two 
  hours 
  after 
  feeding 
  

   they 
  will 
  be 
  found 
  to 
  be 
  ravenously 
  hungry, 
  and 
  they 
  grow 
  much, 
  faster 
  

   for 
  frequent 
  feeding 
  and 
  get 
  that 
  growth 
  in 
  their 
  infancy 
  which 
  is 
  

   indispensable 
  to 
  their 
  ultimately 
  attaining 
  the 
  largest 
  possible 
  size. 
  If 
  

   they 
  are 
  not 
  fed 
  very 
  often 
  they 
  will 
  bite 
  at 
  one 
  another's 
  fins 
  and 
  so 
  

   cause 
  more 
  or 
  less 
  mortality 
  among 
  themselves. 
  

  

  ARTIFICIAL 
  FOOD. 
  

  

  The 
  best 
  food 
  for 
  salmon 
  fry 
  is 
  some 
  kind 
  of 
  meat, 
  finely 
  pulverized. 
  

   Boiled 
  liver 
  is 
  especially 
  good 
  for 
  this 
  purpose, 
  partly 
  because 
  it 
  is 
  

   inexpensive 
  and 
  easily 
  obtainable, 
  and 
  also 
  because 
  it 
  can 
  be 
  separated 
  

   into 
  very 
  fine 
  particles. 
  Kaw 
  liver 
  is 
  also 
  an 
  excellent 
  food 
  for 
  fry, 
  

   and 
  may 
  be 
  reduced 
  into 
  as 
  fine 
  particles 
  as 
  the 
  cooked 
  liver 
  by 
  grind- 
  

   ing 
  or 
  chopping 
  and 
  then 
  properly 
  straining 
  it 
  through 
  a 
  fine-mesh 
  

  

  