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  Geological 
  'Survey 
  of 
  IvOuisiana 
  [Sect. 
  

  

  Section 
  of 
  Hole 
  No. 
  8. 
  — 
  Altogether 
  eight 
  holes 
  were 
  drilled 
  to 
  

   locate 
  the 
  contour 
  of 
  the 
  salt. 
  Only 
  four 
  of 
  these 
  reached 
  the 
  

   salt. 
  They 
  all 
  show 
  a 
  surface 
  layer 
  of 
  clay 
  from 
  33 
  to 
  no 
  feet 
  

   thick 
  beneath 
  which 
  are 
  irregular 
  layers 
  of 
  sand 
  and 
  gravel 
  with 
  

   one 
  or 
  more 
  layers 
  of 
  blue 
  clay, 
  and 
  in 
  one 
  case 
  a 
  thin 
  layer 
  of 
  

   lignite. 
  The 
  nearest 
  the 
  salt 
  approaches 
  the 
  surface 
  is 
  91 
  feet, 
  

   in 
  hole 
  No. 
  8 
  which 
  showed 
  the 
  following 
  section 
  : 
  

  

  Section 
  of 
  Hole 
  No. 
  8 
  

   No. 
  Depths 
  Feet 
  

  

  I. 
  o- 
  33 
  Clay 
  33 
  

  

  2- 
  33- 
  91 
  Sand 
  and 
  clay 
  58 
  

  

  3. 
  91-112 
  Rock 
  salt, 
  not 
  passed 
  through 
  21 
  

  

  Blue 
  clay 
  a^id 
  zinc. 
  — 
  In 
  hole 
  No. 
  7, 
  a 
  depth 
  of 
  442 
  feet 
  was 
  

  

  reached 
  without 
  finding 
  salt. 
  This 
  shows 
  fairly 
  well 
  the 
  usual 
  

  

  arrangement 
  of 
  the 
  beds 
  on 
  the 
  island. 
  

  

  Section 
  of 
  Hole 
  No. 
  7 
  

   No. 
  Depths 
  Feet 
  

  

  1. 
  o- 
  80 
  Clay 
  80 
  

  

  2. 
  80-187 
  Sand 
  107 
  

  

  3. 
  187-195 
  Sand 
  and 
  blue 
  clay 
  8 
  

  

  4. 
  195-260 
  Sand 
  65 
  

  

  5. 
  260-278 
  Sand 
  and 
  gravel 
  18 
  

  

  6. 
  278-303 
  Coarse 
  gravel 
  25 
  

  

  7- 
  303~363 
  Sand 
  and 
  gravel 
  60 
  

  

  8. 
  363-396 
  Blue 
  cla}^ 
  and 
  zinc 
  sand 
  33 
  

  

  9. 
  396-428 
  Sand 
  32 
  

  

  10. 
  428-442 
  Cemented 
  sand 
  and 
  blue 
  clay 
  * 
  16 
  

  

  In 
  layer 
  2, 
  at 
  a 
  depth 
  of 
  between 
  130 
  and 
  160 
  feet, 
  a 
  fragment 
  

   of 
  pottery 
  2x3 
  inches 
  was 
  pumped 
  out 
  of 
  the 
  pipe. 
  It 
  is 
  posi- 
  

   tively 
  stated 
  that 
  it 
  could 
  not 
  have 
  fallet; 
  in 
  from 
  above. 
  Layer 
  

   8 
  records 
  the 
  blue 
  galena 
  and 
  zinc 
  clay 
  of 
  Belle 
  Isle. 
  

  

  Shape 
  of 
  Salt 
  Mass. 
  — 
  At 
  the 
  time 
  of 
  the 
  writer's 
  visit 
  there 
  

   was 
  no 
  one 
  on 
  the 
  island 
  who 
  could 
  give 
  the 
  exact 
  location 
  or 
  

   order 
  of 
  the 
  holes. 
  It 
  was 
  therefore 
  impossible 
  to 
  determine 
  

   their 
  relative 
  position 
  and 
  elevation. 
  This 
  leaves 
  us 
  decidedly 
  

   in 
  the 
  dark 
  as 
  to 
  the 
  exact 
  shape 
  of 
  the 
  salt 
  mass. 
  All 
  that 
  we 
  

   know 
  is 
  that 
  there 
  is 
  a 
  point 
  of 
  maximum 
  elevation. 
  

  

  *To 
  this 
  Mr. 
  Lucas 
  adds 
  " 
  Salt 
  is 
  probably 
  not 
  very 
  far 
  from 
  this 
  point." 
  

  

  