﻿LOBSTER 
  AND 
  CLAM 
  INVESTIGATIONS. 
  159 
  

  

  fouled 
  the 
  water. 
  The 
  subject 
  of 
  food 
  and 
  the 
  method 
  of 
  feeding 
  will 
  

   be 
  discussed 
  later. 
  

  

  6. 
  Constant 
  agitation 
  of 
  the 
  water 
  is 
  the 
  most 
  important 
  factor 
  in 
  

   lobster 
  rearing, 
  and 
  Doctor 
  Mead's 
  fortunate 
  discovery 
  of 
  this 
  fact 
  

   marked 
  the 
  course 
  of 
  future 
  experiments. 
  

  

  WORK 
  DURING 
  1901. 
  

  

  Since 
  it 
  appeared 
  from 
  the 
  investigations 
  of 
  1900 
  that 
  young 
  lobsters 
  

   thrive 
  better 
  at 
  Wickford 
  than 
  at 
  other 
  localities 
  in 
  New 
  England, 
  the 
  

   special 
  commission 
  decided 
  to 
  abandon 
  for 
  the 
  season 
  its 
  other 
  stations 
  

   and 
  concentrate 
  its 
  energies 
  at 
  Wickford. 
  Again 
  the 
  Rhode 
  Island 
  

   Commission 
  of 
  Inland 
  Fisheries 
  most 
  cordially 
  cooperated 
  with 
  the 
  

   government, 
  offered 
  the 
  use 
  of 
  its 
  floating 
  laboratory 
  with 
  its 
  equip- 
  

   ment, 
  and 
  facilitated 
  the 
  carrying 
  out 
  of 
  the 
  experiments 
  in 
  every 
  

   way 
  possible. 
  

  

  The 
  application 
  of 
  the 
  most 
  important 
  result 
  of 
  the 
  preceding 
  3'ear 
  

   (1900) 
  was 
  the 
  first 
  consideration. 
  Constant 
  agitation 
  of 
  the 
  water, 
  

   very 
  diflerent, 
  however, 
  from 
  that 
  obtained 
  in 
  the 
  McDonald 
  hatching 
  

   jar, 
  was 
  a 
  prime 
  necessity, 
  and 
  the 
  commission 
  decided 
  to 
  provide 
  

   some 
  mechanical 
  device 
  to 
  replace 
  the 
  laborious 
  and 
  unsatisfactory 
  

   method 
  of 
  stirring 
  used 
  in 
  the 
  test 
  experiments. 
  

  

  The 
  last 
  week 
  in 
  April 
  the 
  writer 
  went 
  to 
  Wickford 
  for 
  the 
  purpose 
  

   of 
  devising 
  and 
  constructing 
  an 
  apparatus 
  suitable 
  for 
  the 
  work. 
  

   Some 
  of 
  the 
  mechanical 
  difficulties 
  were 
  peculiar, 
  and 
  of 
  the 
  devices 
  

   suggested 
  some 
  modification 
  of 
  a 
  propeller 
  movement 
  seemed 
  most 
  

   feasil)le. 
  Tlie 
  floating 
  laborator^^ 
  or 
  house 
  boat 
  proved 
  an 
  admirable 
  

   place 
  for 
  constructing 
  the 
  apparatus. 
  The 
  house 
  boat, 
  with 
  a 
  house 
  

   at 
  each 
  end, 
  was 
  a 
  kind 
  of 
  catamaran, 
  consisting 
  of 
  Iavo 
  large 
  pon- 
  

   toons, 
  68 
  feet 
  long 
  and 
  4 
  feet 
  wide, 
  placed 
  8 
  feet 
  apart. 
  The 
  pontoons 
  

   and 
  the 
  two 
  houses 
  inclose 
  a 
  "well" 
  8 
  feet 
  wide 
  and 
  about 
  25 
  feet 
  

   long. 
  The 
  boat 
  possessed 
  the 
  necessary 
  rigidity 
  to 
  protect 
  the 
  appa- 
  

   ratus 
  from 
  the 
  effects 
  of 
  storm 
  or 
  wind, 
  while 
  the 
  houses 
  furnished 
  

   shelter 
  for 
  the 
  engine 
  and 
  attendants. 
  

  

  The 
  rearing 
  device, 
  a 
  detailed 
  description 
  of 
  which 
  is 
  given 
  below, 
  

   consisted 
  of 
  a 
  series 
  of 
  cylindrical 
  scrim 
  bags 
  supported 
  in 
  a 
  wooden 
  

   frame. 
  In 
  each 
  bag, 
  near 
  the 
  bottom, 
  was 
  placed 
  a 
  two-bladed 
  fan 
  or 
  

   propeller, 
  the 
  vertical 
  shaft 
  of 
  which 
  was 
  connected 
  with 
  a 
  horizontal 
  

   shaft 
  on 
  the 
  deck 
  of 
  the 
  house 
  boat. 
  This 
  shaft 
  was 
  geared 
  to 
  a 
  gaso- 
  

   line 
  engine, 
  which 
  furnished 
  the 
  power. 
  Rotation 
  of 
  the 
  fans 
  created 
  

   a 
  current 
  of 
  water 
  from 
  the 
  bottom 
  of 
  the 
  bag 
  toward 
  the 
  top. 
  

  

  The 
  apparatus 
  ma}^ 
  he 
  described 
  as 
  consisting 
  of 
  two 
  parts: 
  

  

  (a) 
  The 
  car 
  or 
  bag 
  for 
  holding 
  the 
  fry, 
  with 
  its 
  supporting 
  frame- 
  

   work; 
  

  

  {7j) 
  The 
  mechanism 
  (propeller, 
  belts, 
  shafting, 
  etc.) 
  for 
  stirring 
  the 
  

   water. 
  

  

  