﻿18 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  

  

  its 
  tail 
  to 
  some 
  part 
  of 
  the 
  corral 
  wliere 
  he 
  can 
  be 
  quickly 
  caught 
  when 
  

   needed. 
  One 
  man 
  presses 
  the 
  eggs 
  from 
  the 
  female 
  securely 
  held 
  in 
  

   the 
  spawning-box, 
  the 
  pan 
  for 
  receiving 
  these 
  being 
  held 
  by 
  another. 
  

   As 
  soon 
  as 
  the 
  eggs 
  are 
  taken, 
  the 
  male 
  is 
  drawn 
  from 
  the 
  pen 
  by 
  the 
  

   rope 
  and 
  held 
  by 
  one 
  man, 
  who 
  takes 
  it 
  by 
  the 
  tail 
  with 
  his 
  left 
  hand, 
  

   its 
  head 
  between 
  or 
  across 
  his 
  knees. 
  With 
  his 
  right 
  hand 
  the 
  milt 
  

   is 
  then 
  pressed 
  from 
  the 
  fish 
  into 
  the 
  pan 
  containing 
  the 
  eggs 
  as 
  soon 
  

   as 
  possible 
  after 
  they 
  are 
  taken. 
  The 
  eggs 
  are 
  taken 
  in 
  a 
  pan 
  without 
  

   any 
  water 
  and 
  milt 
  enough 
  is 
  used 
  to 
  insure 
  its 
  coming 
  in 
  contact 
  

   with 
  each 
  egg. 
  After 
  the 
  eggs 
  and 
  milt 
  are 
  obtained 
  the 
  pan 
  is 
  gently 
  

   tilted 
  from 
  side 
  to 
  side 
  and 
  the 
  mass 
  of 
  eggs 
  and 
  milt 
  stirred 
  with 
  the 
  

   fingers 
  until 
  it 
  is 
  thoroughly 
  mixed. 
  The 
  pan 
  is 
  then 
  filled 
  about 
  two- 
  

   thirds 
  full 
  of 
  water 
  and 
  left 
  until 
  the 
  eggs 
  separate, 
  the 
  time 
  varying 
  

   from 
  1 
  to 
  1^ 
  hours, 
  according 
  to 
  the 
  number 
  of 
  eggs 
  and 
  the 
  condition 
  

   of 
  the 
  atmosphere. 
  

  

  After 
  the 
  eggs 
  cease 
  to 
  stick 
  to 
  each 
  other 
  and 
  to 
  the 
  sides 
  of 
  the 
  pan 
  

   they 
  are 
  washed 
  clean 
  by 
  repeated 
  rinsings 
  and 
  taken 
  to 
  the 
  hatching- 
  

   house, 
  where 
  they 
  are 
  measured 
  and 
  put 
  in 
  troughs. 
  The 
  percentage 
  

   of 
  eggs 
  impregnated 
  varies 
  with 
  different 
  seasons, 
  places, 
  and 
  methods 
  

   of 
  handling, 
  but 
  it 
  is 
  safe 
  to 
  say 
  that 
  90 
  per 
  cent 
  of 
  the 
  eggs 
  taken 
  are 
  

   impregnated. 
  

  

  The 
  eggs 
  of 
  the 
  quinnat 
  salmon 
  are 
  of 
  a 
  deep 
  salmon-red 
  color. 
  They 
  

   are 
  heavier 
  than 
  water. 
  Their 
  size 
  varies 
  somewhat, 
  but 
  averages 
  about 
  

   -^ 
  or 
  ^e 
  of 
  an 
  inch 
  ; 
  from 
  12 
  to 
  18 
  are 
  covered 
  by 
  a 
  square 
  inch. 
  The 
  

   number 
  in 
  a 
  quart 
  is 
  about 
  3,700. 
  

  

  HATCHING 
  APPARATUS 
  AND 
  METHODS. 
  

  

  The 
  hatching 
  apparatus 
  generally 
  employed 
  on 
  the 
  Pacific 
  coast 
  in 
  

   salmon 
  propagation 
  consists 
  of 
  a 
  combination 
  of 
  troughs 
  and 
  baskets. 
  

   The 
  troughs 
  in 
  common 
  use 
  are 
  the 
  so-called 
  "Williamson 
  troughs," 
  

   which 
  are 
  16 
  feet 
  long, 
  12 
  or 
  16 
  inches 
  wide, 
  and 
  6^ 
  inches 
  deep. 
  The 
  

   troughs 
  are 
  arranged 
  in 
  pairs, 
  and 
  usually 
  two 
  or 
  three 
  pairs 
  are 
  placed 
  

   end 
  to 
  end 
  on 
  different 
  levels. 
  The 
  fall 
  of 
  water 
  in 
  each 
  trough 
  is 
  1^ 
  

   inches. 
  The 
  troughs 
  are 
  divided 
  by 
  double 
  partitions 
  of 
  wood 
  or 
  metal 
  

   into 
  com;)artments 
  just 
  enough 
  longer 
  than 
  the 
  baskets 
  to 
  enable 
  the 
  

   latter 
  to 
  be 
  raised 
  and 
  lowered 
  and 
  to 
  be 
  tilted 
  slightly. 
  The 
  essential 
  

   feature 
  of 
  these 
  troughs 
  is 
  thait 
  at 
  the 
  lower 
  end 
  of 
  each 
  compartment 
  

   a 
  partition, 
  extending 
  entirely 
  across 
  the 
  trough, 
  reaches 
  from 
  the 
  

   bottom 
  almos-t 
  to 
  the 
  top, 
  and 
  another 
  similar 
  partition 
  at 
  the 
  upper 
  

   end 
  of 
  the 
  compartment 
  reaches 
  from 
  the 
  top 
  almost 
  to 
  the 
  bottom 
  of 
  the 
  

   trough, 
  each 
  set 
  of 
  partitions 
  being 
  about 
  an 
  inch 
  apart. 
  The 
  water 
  

   is 
  consequently 
  forced 
  to 
  fiow 
  under 
  the 
  upper 
  partition 
  and 
  over 
  the 
  

   lower 
  partition, 
  and 
  in 
  order 
  to 
  do 
  this 
  it 
  must 
  necessarily 
  ascend 
  

   through 
  the 
  tray 
  of 
  eggs 
  The 
  troughs 
  are 
  provided 
  with 
  covers 
  made 
  

   of 
  canvas 
  stretched 
  upon 
  light 
  frames, 
  and 
  made 
  sunlight 
  proof 
  by 
  

   saturation 
  with 
  asphaltum 
  varnish. 
  The 
  interior 
  of 
  the 
  troughs 
  is 
  

   thickly 
  coated 
  with 
  asphaltum. 
  

  

  