﻿[17] 
  

  

  ON 
  DEEP-SEA 
  DEPOSITS. 
  

  

  775 
  

  

  pearing 
  with 
  a 
  browner 
  tinge, 
  but 
  these 
  spots 
  are 
  noticed 
  gradually 
  to 
  

   disappear 
  in 
  the 
  surrounding 
  mass. 
  The 
  coloration 
  given 
  by 
  the 
  man- 
  

   ganese 
  is 
  much 
  more 
  distinct. 
  There 
  are 
  small, 
  rounded 
  . 
  brownish 
  

   spots 
  with 
  a 
  diameter 
  of 
  less 
  than 
  0.01 
  mm 
  , 
  which 
  disappear 
  under 
  the 
  

   action 
  of 
  hydrochloric 
  acid 
  with 
  disengagement 
  of 
  chlorine. 
  These 
  

   small 
  round 
  concretions, 
  which 
  are 
  probably 
  a 
  mixture 
  of 
  the 
  oxides 
  

   of 
  iron 
  and 
  manganese, 
  will 
  be 
  described 
  with 
  more 
  detail 
  in 
  the 
  Chal- 
  

   lenger 
  report. 
  

   The 
  following 
  table 
  shows 
  the 
  nomenclature 
  we 
  have 
  adopted 
  : 
  

  

  Terrigenous 
  

   Deposits. 
  

  

  ^ 
  Shore 
  formations, 
  

   Blue 
  mud, 
  

  

  Green 
  mud 
  and 
  sand. 
  

   Red 
  mud, 
  

  

  ~) 
  Found 
  in 
  inland 
  

   seas 
  and 
  along 
  

   the 
  shores 
  of 
  

   continents. 
  

  

  !* 
  

  

  Coral 
  mud 
  and 
  sand, 
  

   Coralline 
  mud 
  and 
  sand, 
  

   Volcanic 
  mud 
  and 
  sand. 
  

  

  Pelagic 
  De- 
  

   posits. 
  

  

  I 
  

  

  ^ 
  Eed 
  clay, 
  

   j 
  Globigerina 
  ooze, 
  

   <^ 
  Pteropod 
  ooze, 
  

   Diatom 
  ooze, 
  

   Eadiolarian 
  ooze, 
  

  

  "} 
  Found 
  about 
  

   oceanic 
  islands 
  

  

  Y 
  and 
  along 
  the 
  

   shores 
  of 
  conti- 
  

  

  3 
  neuts. 
  

  

  1 
  

  

  3 
  

  

  Found 
  in 
  the 
  

   abysmal 
  regions 
  

   of 
  the 
  ocean 
  ba- 
  

   sins. 
  

  

  Geographical 
  and 
  bathymetrical 
  distribution. 
  — 
  In 
  the 
  pre- 
  

   ceding 
  pages 
  we 
  have 
  confined 
  our 
  remarks 
  essentially 
  to 
  the 
  litholog- 
  

   ical 
  nature 
  of 
  the 
  deep-sea 
  deposits, 
  including 
  in 
  this 
  term 
  the 
  dead 
  

   shells 
  and 
  skeletons 
  of 
  organisms. 
  From 
  this 
  point 
  of 
  view 
  it 
  has 
  been 
  

   possible 
  to 
  define 
  the 
  sediments 
  and 
  to 
  give 
  them 
  distinctive 
  names. 
  

   We 
  now 
  proceed 
  to 
  consider 
  their 
  geographical 
  and 
  bathymetrical 
  dis- 
  

   tribution, 
  and 
  the 
  relations 
  which 
  exist 
  between 
  the 
  mineralogical 
  and 
  

   organic 
  composition 
  and 
  the 
  different 
  areas 
  of 
  the 
  ocean 
  in 
  which 
  they 
  

   are 
  formed. 
  

  

  A 
  cursory 
  glance 
  at 
  the 
  geographical 
  distribution 
  shows 
  that 
  the 
  de- 
  

   posits 
  which 
  we 
  have 
  designated 
  muds 
  and 
  sands 
  are 
  situated, 
  at 
  various 
  

   depths, 
  at 
  no 
  great 
  distance 
  from 
  the 
  land, 
  while 
  the 
  organic 
  oozes 
  and 
  

   red 
  clays 
  occupy 
  the 
  abysmal 
  regions 
  of 
  the 
  ocean 
  basins 
  far 
  from 
  land. 
  

   Leaving 
  out 
  of 
  view 
  the 
  coral 
  and 
  volcanic 
  muds 
  and 
  sands 
  which 
  are 
  

   found 
  principally 
  around 
  oceanic 
  islands, 
  we 
  notice 
  that 
  our 
  blue 
  muds, 
  

   green 
  muds 
  and 
  sands, 
  red 
  muds, 
  together 
  with 
  all 
  the 
  coast 
  and 
  snore 
  

   formations, 
  are 
  situated 
  along 
  the 
  margins 
  of 
  the 
  continents 
  and 
  in 
  in- 
  

   closed 
  and 
  partially 
  inclosed 
  seas. 
  The 
  chief 
  characteristic 
  of 
  these 
  de- 
  

   posits 
  is 
  the 
  presence 
  in 
  them 
  of 
  continental 
  debris. 
  The 
  blue 
  muds 
  are 
  

   found 
  in 
  all 
  the 
  deeper 
  parts 
  of 
  the 
  regions 
  just 
  indicated, 
  and 
  especially 
  

   near 
  the 
  embouchures 
  of 
  rivers. 
  Eed 
  muds 
  do 
  not 
  differ 
  much 
  from 
  

   blue 
  muds 
  except 
  in 
  color, 
  due 
  to 
  the 
  presence 
  of 
  ferruginous 
  matter 
  in 
  

   great 
  abundance, 
  and 
  we 
  find 
  them 
  under 
  the 
  same 
  conditions 
  as 
  the 
  

  

  