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  The 
  number 
  of 
  oysters 
  would 
  then, 
  on 
  a 
  limited 
  bed, 
  steadily 
  

   increase, 
  as 
  long 
  as 
  there 
  was 
  sufficient 
  room 
  and 
  food 
  supplied 
  

   them, 
  until 
  they 
  had 
  reached 
  their 
  limit, 
  a 
  rather 
  indefinable 
  one 
  

   in 
  that 
  direction, 
  the 
  quality 
  of 
  the 
  oysters 
  not 
  being 
  taken 
  

   into 
  consideration. 
  Having 
  reached 
  that 
  point, 
  the 
  nura])er 
  

   of 
  oysters 
  would 
  to 
  all 
  intents 
  remain 
  the 
  same 
  as 
  long 
  as 
  the 
  

   conditions 
  under 
  which 
  they 
  had 
  previously 
  lived 
  were 
  not 
  

   changed. 
  To 
  cause, 
  then, 
  either 
  an 
  increase 
  or 
  diminution 
  of 
  

   the 
  number 
  of 
  oysters 
  or 
  size 
  of 
  the 
  bed, 
  a 
  new 
  factor 
  must 
  

   be 
  brought 
  in, 
  when, 
  all 
  conditions 
  being 
  changed, 
  the 
  life 
  of 
  

   the 
  animals 
  begins 
  anew 
  and 
  progresses 
  differently. 
  As 
  there 
  

   can 
  be 
  no 
  doubt 
  that 
  both 
  the 
  beds 
  and 
  oysters 
  of 
  Tangiei' 
  and 
  

   Pocomoke 
  Sounds 
  have 
  changed 
  greatly 
  in 
  character 
  since 
  

   their 
  first 
  discovery, 
  in 
  accounting 
  for 
  that 
  change 
  it 
  is 
  neces- 
  

   sary 
  to 
  discover 
  the 
  new 
  factor 
  or 
  factors 
  that 
  have 
  been 
  intro- 
  

   duced, 
  and 
  that 
  have 
  been 
  instrumental 
  in 
  effecting 
  it. 
  Briefly, 
  

   the 
  change 
  in 
  the 
  beds 
  has 
  been 
  a 
  material 
  expansion 
  of 
  their 
  

   limits 
  and 
  a 
  material 
  diminution 
  of 
  the 
  number 
  of 
  oysters 
  upon 
  

   them, 
  and 
  therefore 
  the 
  causes 
  for 
  such 
  changes 
  must 
  be 
  sought 
  

   among 
  such 
  as 
  it 
  is 
  known 
  would 
  produce 
  like 
  eftects. 
  

  

  Disregarding 
  for 
  the 
  present 
  the 
  agency 
  of 
  man 
  in 
  the 
  mat- 
  

   ter, 
  the 
  question 
  is 
  what 
  natural 
  cause 
  or 
  causes 
  would 
  both 
  

   expand 
  the 
  beds 
  and 
  diminish 
  the 
  number 
  of 
  oysters? 
  A 
  

   bed 
  is 
  extended 
  naturally 
  by 
  the 
  drifting 
  spat 
  or 
  "young 
  

   brood 
  " 
  attaching 
  themselves 
  to 
  any 
  clean, 
  hard 
  and 
  moder- 
  

   ately 
  rough 
  substance 
  contiguous 
  to 
  the 
  bed. 
  The 
  locomo- 
  

   tive 
  powers 
  of 
  the 
  " 
  spat 
  " 
  exist 
  for 
  but 
  a 
  short 
  time 
  and, 
  

   except 
  when 
  assisted 
  by 
  the 
  current, 
  they 
  can 
  only 
  move 
  a 
  

   short 
  distance, 
  and 
  unless 
  some 
  suitable 
  object 
  soon 
  presents 
  

   itself 
  for 
  their 
  attachment 
  they 
  will 
  sink 
  into 
  the 
  soft 
  bottoms 
  

   and 
  die. 
  The 
  principal 
  expansion 
  of 
  the 
  beds 
  so 
  far 
  as 
  could 
  

   be 
  effected 
  by 
  nature 
  must, 
  however, 
  have 
  been 
  accomplished 
  

   long 
  ago, 
  the 
  beds 
  being 
  surrounded 
  originally, 
  and 
  indeed 
  

   at 
  present, 
  by 
  soft 
  bottoms 
  of 
  a 
  character 
  which 
  would 
  be 
  

   most 
  destructive 
  to 
  the 
  " 
  brood," 
  unless 
  some 
  substance 
  was 
  

   interposed 
  between 
  it 
  and 
  them 
  for 
  their 
  reception. 
  Natural 
  

   expansion 
  can 
  only 
  be 
  achieved 
  to 
  any 
  extent 
  in 
  the 
  manner 
  

   described, 
  and 
  though 
  probably 
  there 
  is, 
  and 
  has 
  been, 
  a 
  slow 
  

  

  