﻿Ill] 
  The 
  Five 
  Islands 
  : 
  Cote 
  Carbine 
  255 
  

  

  Topography 
  . 
  — 
  The 
  area 
  of 
  this 
  circular 
  protuberance 
  in 
  the 
  

   prairie 
  is 
  about 
  300 
  acres. 
  It 
  is 
  very 
  regular 
  with 
  a 
  maximum 
  

   diameter 
  of 
  about 
  a 
  mile. 
  Facing 
  the 
  lake 
  is 
  a 
  little 
  wave- 
  

   formed 
  bluff 
  about 
  thirty 
  feet 
  high. 
  With 
  this 
  exception 
  the 
  

   slope 
  from 
  the 
  highest 
  point, 
  which 
  has 
  an 
  elevation 
  of 
  75 
  feet 
  

   above 
  the 
  lake 
  just 
  back 
  of 
  the 
  Jefferson 
  residence, 
  is 
  very 
  

   gradual. 
  The 
  hollows 
  are 
  very 
  insignificant. 
  

  

  Geoi,ogy 
  

  

  Surface 
  geology. 
  — 
  It 
  is 
  this 
  little 
  bluff 
  which 
  Thomassy 
  mentions 
  

  

  in 
  his 
  description 
  of 
  the 
  island 
  and 
  lyake 
  Peigneur 
  is 
  the 
  

  

  ' 
  ' 
  ancient 
  crater 
  ' 
  ' 
  from 
  which 
  he 
  supposed 
  the 
  material 
  forming 
  

  

  C6te 
  Carline 
  was 
  thrown 
  out. 
  Hilgard 
  did 
  not 
  visit 
  the 
  island 
  

  

  and 
  was 
  unable 
  to 
  locate 
  the 
  ' 
  ' 
  central 
  crater 
  ' 
  ' 
  from 
  descriptions 
  

  

  received 
  because 
  he 
  was 
  evidently 
  looking 
  for 
  a 
  small 
  lake 
  on 
  the 
  

  

  island 
  itself 
  like 
  those 
  on 
  Petite 
  Anse 
  and 
  Grande 
  Cote. 
  

  

  Although 
  Thomassy 
  's 
  conclusions 
  were 
  a 
  little 
  distorted 
  his 
  

  

  observations 
  were 
  in 
  the 
  main 
  very 
  correct. 
  

  

  Bhiff 
  section. 
  — 
  The 
  bluff 
  sections 
  which 
  he 
  describes 
  shows 
  : 
  

  

  Feet 
  

  

  1. 
  Surface 
  soil 
  2 
  

  

  2. 
  lyight 
  yellow 
  buckshot 
  clay 
  with 
  limestone 
  concretions 
  . 
  26 
  

  

  3. 
  Gravel 
  to 
  water 
  level 
  2 
  

  

  The 
  surface 
  of 
  the 
  island 
  is 
  uniformly 
  covered 
  with 
  a 
  humus- 
  

   stained 
  yellow 
  loam 
  containing 
  limestone 
  concretions. 
  The 
  only 
  

   exposure 
  of 
  gravel 
  is 
  along 
  the 
  shore 
  of 
  the 
  lake 
  at 
  the 
  base 
  of 
  

   the 
  cliff. 
  Numerous 
  springs 
  issue 
  from 
  the 
  gravel 
  bed. 
  

  

  Salt 
  explorations. 
  — 
  In 
  1894 
  Mr. 
  Jefferson 
  let 
  a 
  contract 
  for 
  

  

  drilling 
  a 
  well 
  near 
  his 
  home, 
  this 
  resulted 
  in 
  the 
  discovery 
  of 
  

  

  rock 
  salt 
  at 
  a 
  depth 
  of 
  334 
  feet 
  early 
  in 
  the 
  summer 
  of 
  1895. 
  

  

  Mr. 
  A. 
  F. 
  lyUcas 
  was 
  then 
  put 
  in 
  charge 
  of 
  the 
  drilling 
  and 
  with 
  

  

  a 
  diamond 
  drill 
  sunk 
  the 
  hole 
  to 
  a 
  depth 
  of 
  2,090 
  feet. 
  The 
  drill 
  

  

  was 
  still 
  in 
  salt 
  when 
  work 
  ceased. 
  The 
  section 
  exposed 
  there 
  

  

  was 
  : 
  

  

  Section 
  of 
  Hole 
  No. 
  / 
  

  

  (Elevation 
  above 
  lake 
  65 
  feet^72 
  feet 
  A. 
  T,?) 
  

  

  . 
  Feet 
  

  

  1. 
  o- 
  265 
  Unknown 
  265 
  

  

  2. 
  265- 
  334 
  Coarse 
  gravel 
  and 
  sand 
  69 
  

  

  3. 
  334-2090 
  White 
  rock 
  salt 
  without 
  noticeable 
  impurities 
  1756 
  

  

  