﻿MANUAL 
  OF 
  FISH-CULTURE. 
  57 
  

  

  into 
  conduits 
  leading 
  to 
  ponds 
  where 
  larger 
  fish 
  are 
  kept 
  ; 
  but 
  a 
  stand 
  of 
  

   100 
  troughs 
  has 
  lately 
  been 
  set 
  up 
  with 
  the 
  design 
  of 
  using 
  all 
  the 
  

   water 
  twice; 
  and 
  for 
  many 
  years 
  there 
  has 
  been 
  one 
  system 
  of 
  52 
  

   troughs, 
  arranged 
  in 
  four 
  series, 
  which 
  use 
  in 
  succession 
  the 
  same 
  

   water, 
  the 
  young 
  salmon 
  thriving 
  quite 
  as 
  well 
  in 
  the 
  fourth 
  series 
  as 
  

   in 
  the 
  first. 
  

  

  On 
  one 
  occasion 
  a 
  few 
  of 
  them 
  were 
  maintained 
  for 
  several 
  weeks 
  in 
  

   the 
  warmer 
  water 
  of 
  a 
  neighboring 
  brook, 
  where 
  a 
  trough 
  was 
  set 
  up 
  

   and 
  stocked 
  with 
  100 
  young 
  salmon 
  taken 
  from 
  one 
  of 
  the 
  troughs 
  at 
  

   the 
  station 
  July 
  30. 
  The 
  temperatures 
  observed 
  between 
  1 
  and 
  4 
  p. 
  m. 
  

   in 
  the 
  fish-trough 
  on 
  successive 
  days 
  from 
  July 
  30 
  to 
  August 
  14, 
  not 
  

   including 
  August 
  1 
  or 
  10, 
  were 
  as 
  follows: 
  79°, 
  75°, 
  77°, 
  79°, 
  82°, 
  82°, 
  

   78°, 
  76°, 
  76°, 
  76°, 
  74°, 
  74°, 
  74°, 
  74°, 
  F. 
  

  

  The 
  fish 
  were 
  fed 
  the 
  same 
  as 
  the 
  lot 
  out 
  of 
  which 
  they 
  were 
  taken, 
  

   except 
  that 
  they 
  received 
  food 
  only 
  once 
  a 
  day 
  instead 
  of 
  twice, 
  and 
  

   were 
  returned 
  to 
  the 
  station 
  October 
  7 
  without 
  a 
  single 
  loss 
  during 
  the 
  

   experiment. 
  Moreover, 
  they 
  were 
  all 
  weighed 
  October 
  10 
  and 
  found 
  

   to 
  average 
  100.6 
  grains, 
  while 
  those 
  of 
  the 
  original 
  lot 
  that 
  had 
  remained 
  

   at 
  the 
  station, 
  with 
  a 
  temperature 
  between 
  50° 
  and 
  71° 
  F., 
  averaged 
  

   only 
  56.1 
  grains. 
  While 
  the 
  greatly 
  increased 
  weight 
  of 
  the 
  fish 
  kept 
  

   in 
  the 
  stream 
  was 
  owing 
  in 
  part 
  to 
  more 
  space, 
  as 
  the 
  100 
  had 
  as 
  large 
  

   a 
  trough 
  as 
  1,505 
  at 
  the 
  station, 
  the 
  higher 
  temperature 
  was 
  undoubt- 
  

   edly 
  one 
  of 
  the 
  factors 
  that 
  contributed 
  to 
  the 
  gain 
  in 
  weight, 
  and 
  it 
  is 
  

   at 
  least 
  plainly 
  shown 
  that 
  the 
  warm 
  water 
  was 
  not 
  unhealthful. 
  

  

  Though 
  small 
  ponds, 
  excavated 
  by 
  the 
  former 
  ijroprietor, 
  were 
  in 
  

   existence 
  at 
  the 
  station 
  and 
  used 
  to 
  some 
  extent 
  for 
  rearing 
  young 
  fish 
  

   in 
  their 
  first 
  summer 
  as 
  far 
  back 
  as 
  1888, 
  and 
  older 
  fish 
  have 
  been 
  kept 
  

   in 
  small 
  ponds 
  each 
  season 
  since 
  that, 
  it 
  was 
  not 
  until 
  1896 
  that 
  enough 
  

   pond 
  work 
  was 
  done 
  to 
  furnish 
  data 
  of 
  importance. 
  

  

  The 
  ponds 
  for 
  rearing 
  Atlantic 
  salmon 
  are 
  among 
  the 
  series 
  known 
  

   as 
  the 
  "south 
  ponds," 
  occupying 
  a 
  smooth 
  piece 
  of 
  ground 
  sloping 
  

   toward 
  Alamoosook 
  Lake 
  at 
  a 
  grade 
  of 
  1 
  in 
  8. 
  Formerly 
  it 
  was 
  mostly 
  a 
  

   swale, 
  watered 
  by 
  a 
  copious 
  spring 
  at 
  its 
  head. 
  This 
  series 
  comprises 
  19 
  

   ponds 
  of 
  rectangular 
  form, 
  about 
  50 
  to 
  90 
  feet 
  long 
  and 
  15 
  feet 
  wide, 
  with 
  

   a 
  depth 
  of 
  2 
  or 
  3 
  feet. 
  The 
  water 
  supply 
  of 
  those 
  used 
  for 
  Atlantic 
  sal- 
  

   mon 
  is 
  derived 
  from 
  Craig 
  Brook 
  by 
  an 
  aqueduct 
  tapping 
  it 
  at 
  a 
  point 
  

   where 
  two 
  parts 
  of 
  Craig 
  Pond 
  water 
  are 
  mingled 
  with 
  one 
  part 
  spring 
  

   water, 
  being 
  substantially 
  the 
  same 
  as 
  the 
  water 
  supplying 
  the 
  most 
  

   of 
  the 
  rearing- 
  troughs. 
  From 
  5,000 
  to 
  10,000 
  fish 
  that 
  have 
  been 
  fed 
  in 
  

   troughs 
  during 
  the 
  early 
  pare 
  of 
  the 
  feeding 
  season 
  are 
  placed 
  in 
  each 
  

   pond, 
  and 
  for 
  the 
  remainder 
  of 
  the 
  season 
  are 
  fed 
  the 
  same 
  food 
  that 
  is 
  

   given 
  to 
  the 
  fish 
  left 
  in 
  the 
  troughs; 
  and 
  the 
  results 
  indicate 
  that 
  the 
  

   stock 
  of 
  fish 
  might 
  be 
  safely 
  increased. 
  

  

  While 
  the 
  greater 
  part 
  of 
  the 
  salmon 
  reared 
  at 
  Craig 
  Brook 
  are 
  

   liberated 
  in 
  October, 
  when 
  about 
  seven 
  months 
  old, 
  in 
  1891-92 
  about 
  

   16,000 
  were 
  carried 
  through 
  the 
  winter, 
  most 
  of 
  them 
  in 
  tanks 
  sunk 
  

   in 
  the 
  ground, 
  and 
  nearly 
  as 
  many 
  have 
  been 
  wintered 
  some 
  other 
  

  

  