﻿109 
  

  

  By 
  consulting 
  the 
  table, 
  it 
  will 
  be 
  seen 
  that 
  the 
  state 
  of 
  the 
  

   tide 
  has 
  but 
  little 
  influence 
  upon 
  the 
  density, 
  though 
  the 
  

   depth 
  of 
  the 
  water 
  has 
  and 
  the 
  prevalence 
  of 
  strong 
  winds 
  

   may 
  increase 
  or 
  diminish 
  it. 
  There 
  is 
  shown 
  a 
  gradual 
  and 
  

   constant 
  increase 
  of 
  density 
  as 
  the 
  southern 
  portion 
  of 
  the 
  

   Sound, 
  where 
  it 
  opens 
  upon 
  the 
  Chesapeake, 
  is 
  approached. 
  

  

  There 
  is 
  also 
  an 
  increase 
  of 
  density 
  when 
  in 
  the 
  vicinity 
  of 
  

   the 
  openings 
  into 
  the 
  Bay 
  and 
  a 
  decrease 
  in 
  the 
  various 
  rivers 
  

   and 
  off 
  their 
  mouths. 
  

  

  Though 
  the 
  density 
  of 
  the 
  w^ater 
  increases, 
  yet 
  the 
  differ- 
  

   ence 
  between 
  the 
  maximum 
  and 
  minimum 
  densities 
  steadily 
  

   decreases 
  to 
  the 
  southward, 
  showing 
  that 
  the 
  oysters 
  on 
  the 
  

   northern 
  beds 
  are 
  exposed 
  to 
  greater 
  fluctuations 
  of 
  density, 
  

   and 
  probably 
  salinity, 
  than 
  those 
  on 
  the 
  beds 
  to 
  the 
  south- 
  

   ward. 
  

  

  There 
  were 
  no 
  heavy 
  rains 
  during 
  my 
  stay 
  in 
  the 
  Sounds 
  

   and 
  the 
  densities 
  given 
  therefore 
  show 
  only 
  the 
  condition 
  of 
  

   the 
  water 
  in 
  that 
  respect 
  during 
  dry 
  weather. 
  I 
  was 
  informed 
  

   that 
  there 
  was 
  a 
  noticeable 
  change 
  in 
  its 
  character 
  about 
  the 
  

   mouths 
  of 
  the 
  tributaries 
  of 
  the 
  Sounds, 
  after 
  a 
  heavy 
  rain- 
  

   fall 
  and 
  the 
  eflect 
  upon 
  the 
  oj^sters 
  was 
  also 
  perceivable. 
  

  

  The 
  difierence 
  between 
  the 
  maximum 
  and 
  minimum 
  densi- 
  

   ties 
  of 
  the 
  Sound 
  amounts 
  to 
  0.0053 
  ; 
  but 
  the 
  difference 
  be- 
  

   tween 
  the 
  maximum 
  and 
  minimum 
  densities 
  on 
  each 
  bed 
  will 
  

   give 
  a 
  more 
  correct 
  idea 
  of 
  the 
  changes 
  to 
  which 
  the 
  oysters 
  

   are 
  exposed. 
  The 
  greatest 
  difterence 
  is 
  0.0025, 
  wdiich 
  takes 
  

   place 
  over 
  the 
  Shark's-Fin 
  and 
  Fishing 
  Bay 
  beds 
  and 
  the 
  least 
  

   difference 
  over 
  any 
  of 
  the 
  main 
  beds 
  is 
  that 
  on 
  the 
  Little 
  

   Thoroughfare, 
  which 
  amounts 
  to 
  0.0009. 
  

  

  It 
  would 
  be 
  perhaps 
  still 
  more 
  correct 
  to 
  divide 
  the 
  Sound 
  

   into 
  several 
  parts 
  and 
  consider 
  the 
  fluctuation 
  of 
  densities 
  

   over 
  them 
  thereby 
  assemblingalargernumber 
  of 
  observations. 
  

  

  Throwing 
  out 
  the 
  Fishiiig 
  Bay 
  beds, 
  which 
  by 
  their 
  po- 
  

   sition 
  are 
  removed 
  to 
  a 
  great 
  extent 
  from 
  the 
  conditions 
  af- 
  

   fecting 
  the 
  other 
  beds 
  and 
  including 
  a-1 
  those 
  south 
  of 
  Clay 
  

   Island 
  as 
  far 
  as 
  Piney 
  Island 
  Bar, 
  when 
  the 
  influence 
  of 
  the 
  

   Manokin 
  and 
  Annemessex 
  Rivers 
  would 
  be 
  felt, 
  the 
  difference 
  

   of 
  density 
  amounts 
  to 
  0.0028. 
  

  

  