﻿GEOLOGY. 
  223 
  

  

  as 
  well 
  as 
  in 
  broken 
  fragments, 
  seen 
  agglutinated 
  to- 
  

   gether, 
  and 
  forming 
  with 
  the 
  associated 
  pebbles, 
  the 
  

   composition 
  of 
  the 
  conglomerate 
  of 
  the 
  locality. 
  

  

  LIMESTONE. 
  

  

  Limestone 
  is 
  not 
  known 
  to 
  make 
  its 
  appearance 
  on 
  

   the 
  Mississippi 
  but 
  at 
  one 
  point. 
  

  

  At 
  Vicksburg, 
  it 
  presents 
  itself 
  in 
  the 
  channel 
  of 
  the 
  

   small 
  stream 
  bordering 
  the 
  city 
  on 
  the 
  north, 
  and 
  in 
  the 
  

   face 
  of 
  the 
  bluff 
  is 
  traceable 
  for 
  half 
  a 
  mile 
  or 
  more 
  

   above. 
  

  

  The 
  stratum 
  appears 
  to 
  repose 
  upon 
  a 
  yellow 
  marl, 
  

   and 
  to 
  be 
  divided 
  by 
  it 
  into 
  three 
  layers 
  of 
  some 
  three 
  

   feet 
  each 
  in 
  thickness, 
  the 
  whole 
  including 
  the 
  inter- 
  

   vening 
  marl, 
  not 
  exceeding 
  ten 
  feet. 
  

  

  The 
  lower 
  member 
  of 
  the 
  stratum, 
  which 
  is 
  of 
  a 
  bluish 
  

   tint, 
  affords 
  an 
  excellent 
  material 
  of 
  variable 
  thickness, 
  

   not 
  exceeding 
  a 
  foot, 
  perhaps, 
  in 
  blocks 
  of 
  any 
  extent. 
  

  

  The 
  upper 
  members 
  consist 
  of 
  a 
  yellowish, 
  imper- 
  

   fectly 
  formed, 
  and 
  perishable 
  rock 
  of 
  little 
  value. 
  

  

  This 
  rock 
  is 
  seen 
  occasionally 
  from 
  Vicksburg, 
  exposed 
  

   along 
  the 
  Walnut 
  Hills 
  to 
  Haynes's 
  Bluff, 
  or 
  Old 
  Fort 
  

   St. 
  Peter's 
  on 
  the 
  Yazoo 
  Eiver, 
  and 
  probably 
  extends 
  

   higher. 
  

  

  Towards 
  the 
  interior, 
  it 
  crosses 
  Big 
  Black 
  River, 
  and 
  

   crops 
  out 
  at 
  Steward's 
  quarry, 
  on 
  the 
  Jackson 
  and 
  

   Vicksburg 
  Railroad, 
  on 
  Section 
  28, 
  Township 
  6, 
  Range 
  2 
  

   W., 
  in 
  Hind's 
  County, 
  a 
  few 
  miles 
  west 
  of 
  Clinton; 
  

   also 
  at 
  Marshall's 
  Quarry, 
  on 
  Section 
  17, 
  Township 
  5, 
  

   Range 
  1 
  W., 
  near 
  the 
  Mississippi 
  Springs. 
  

  

  It 
  occurs 
  again 
  at 
  the 
  former 
  quarry 
  of 
  the 
  late 
  John 
  

  

  