﻿220 
  GEOLOGY. 
  

  

  It 
  is 
  seen 
  in 
  the 
  eastern 
  part 
  of 
  Lafayette 
  County, 
  on 
  

   the 
  road 
  leading 
  to 
  Pontotoc. 
  

  

  In 
  Panola 
  County, 
  and 
  in 
  Tallahatchie 
  County, 
  it 
  is 
  

   of 
  frequent 
  occurrence. 
  

  

  All 
  the 
  stone 
  of 
  this 
  character, 
  seen 
  north 
  of 
  the 
  Tal- 
  

   lahatchie, 
  exhibits 
  more 
  or 
  less 
  mica 
  in 
  its 
  composition. 
  

   The 
  mica, 
  not 
  noticed 
  south 
  of 
  this 
  was 
  also 
  observed 
  in 
  

   the 
  sands 
  and 
  clays 
  in 
  Marshall 
  County. 
  

  

  These 
  are 
  a 
  few 
  of 
  the 
  localities 
  in 
  which 
  this 
  Iron 
  

   sandstone 
  is 
  most 
  conspicuous. 
  

  

  But 
  I 
  have 
  nowhere 
  met 
  with 
  it 
  more 
  massive 
  and 
  

   abundant 
  than 
  near 
  Grenada 
  in 
  Yellobusha 
  County. 
  

   Some 
  of 
  the 
  conical 
  peaks 
  of 
  the 
  hills 
  are 
  there 
  covered 
  

   or 
  paved 
  with 
  it, 
  in 
  rounded 
  mammillary 
  and 
  botroidal 
  

   forms. 
  

  

  Very 
  frequently 
  it 
  occurs 
  in 
  the 
  characters 
  of 
  a 
  con- 
  

   glomerate 
  or 
  pudding 
  stone 
  — 
  a 
  concrete 
  formed 
  of 
  the 
  

   rounded 
  cherty 
  pebbles 
  of 
  the 
  drift, 
  and 
  either 
  massive 
  

   or 
  in 
  thin 
  and 
  widely 
  spread 
  sheets, 
  the 
  latter 
  forming 
  a 
  

   species 
  of 
  hard 
  pan, 
  in 
  which 
  latter 
  character 
  it 
  is 
  found 
  

   resting 
  upon 
  beds 
  of 
  Yellow 
  Ochre, 
  as 
  at 
  the 
  base 
  of 
  the 
  

   Natchez 
  Bluffs, 
  and 
  again 
  twelve 
  miles 
  below, 
  at 
  the 
  

   White 
  Cliffs 
  on 
  the 
  Mississippi. 
  

  

  At 
  the 
  latter 
  point, 
  this 
  rock 
  presents 
  another 
  cha- 
  

   racter, 
  and 
  affords 
  a 
  rare 
  exhibition 
  of 
  fulgorites 
  on 
  a 
  

   magnificent 
  scale; 
  the 
  tubes 
  singly 
  or 
  grouped 
  together 
  

   in 
  great 
  masses, 
  of 
  large 
  caliber 
  and 
  considerable 
  length, 
  

   resembling 
  cannon 
  or 
  organ-pipes. 
  These 
  tubes, 
  how- 
  

   ever, 
  are 
  of 
  many 
  sizes, 
  varying 
  from 
  an 
  inch 
  to 
  a 
  foot 
  

   or 
  more 
  in 
  diameter. 
  

  

  A 
  few 
  miles 
  north 
  of 
  Ripley, 
  in 
  Tippah 
  County, 
  on 
  a 
  

   ridge 
  where 
  this 
  ferruginous 
  sandstone 
  abounds, 
  fulgo- 
  

   rites, 
  of 
  a 
  smaller 
  size 
  than 
  those 
  of 
  the 
  White 
  Cliffs, 
  are 
  

   numerous, 
  and 
  appear 
  to 
  have 
  been 
  collected, 
  with 
  otlier 
  

  

  