﻿238 
  GEOLOGY. 
  

  

  specimens 
  of 
  it 
  for 
  the 
  cabinets 
  at 
  Jackson 
  and 
  Oxford, 
  

   where 
  they 
  may 
  be 
  seen. 
  

  

  When 
  quite 
  moist 
  or 
  newly 
  taken 
  from 
  the 
  water, 
  it 
  

   is 
  quite 
  sooty 
  in 
  its 
  character, 
  soiUng 
  the 
  hands 
  equally 
  

   as 
  much, 
  and 
  its 
  whole 
  appearance 
  seemed 
  to 
  answer 
  

   the 
  description 
  of 
  the 
  Erdkohle 
  of 
  Werner. 
  Dried 
  in 
  

   the 
  shade, 
  it 
  loses 
  the 
  smutty 
  property 
  in 
  a 
  considera- 
  

   ble 
  degree, 
  and 
  becomes 
  comparatively 
  compact 
  ; 
  exposed 
  

   in 
  a 
  moist 
  state 
  to 
  the 
  sun, 
  it 
  tlakes 
  off 
  and 
  falls 
  to 
  

   powder. 
  

  

  The 
  bed 
  forms 
  the 
  base 
  to 
  the 
  talus 
  of 
  the 
  river 
  bluffs, 
  

   and 
  is 
  of 
  course 
  covered 
  to 
  within 
  a 
  short 
  distance 
  of 
  

   the 
  w^ater's 
  edge, 
  or 
  to 
  that 
  portion 
  of 
  it 
  recently 
  swept 
  

   by 
  the 
  current 
  of 
  the 
  river, 
  with 
  the 
  detritus 
  whicli 
  

   crumbles 
  from 
  the 
  sides 
  of 
  the 
  bluff, 
  consisting 
  in 
  the 
  

   inferior 
  portion 
  of 
  the 
  mass, 
  of 
  a 
  dark 
  brown 
  shaly 
  

   clay, 
  saturated 
  with 
  sulphate 
  of 
  iron, 
  resulting 
  from 
  the 
  

   decomposition 
  of 
  pyrites, 
  the 
  clay 
  being 
  so 
  highly 
  

   charged 
  with 
  the 
  mineral 
  as 
  to 
  exhibit 
  in 
  dry 
  weather 
  a 
  

   white 
  efflorescence 
  on 
  the 
  surface, 
  resembling 
  frost. 
  

  

  Sharks' 
  teeth, 
  large 
  oyster 
  shells, 
  madrepores, 
  and 
  the 
  

   eocene 
  shells 
  of 
  the 
  formation 
  washed 
  from 
  the 
  upper 
  

   strata, 
  are 
  intermixed 
  and 
  imposed 
  upon 
  the 
  shale. 
  

  

  The 
  thickness 
  of 
  the 
  bed 
  I 
  had 
  no 
  means 
  of 
  ascer- 
  

   taining, 
  no 
  excavation 
  having 
  been 
  made; 
  the 
  outer 
  

   edge 
  terminates 
  abruptly, 
  and 
  the 
  perpendicular 
  face 
  is 
  

   washed 
  by 
  the 
  river, 
  which 
  flows 
  along 
  the 
  margin 
  to 
  a 
  

   great 
  depth. 
  

  

  I 
  observe 
  that 
  the 
  proprietor 
  of 
  this 
  bed, 
  who 
  resides 
  

   in 
  Virginia, 
  is 
  making 
  arrangements 
  for 
  sinking 
  a 
  shaft, 
  

   and 
  testing 
  its 
  quality. 
  

  

  All 
  the 
  other 
  beds 
  of 
  lignite 
  which 
  I 
  have 
  observed, 
  

   or 
  the 
  existence 
  of 
  wdiich 
  I 
  have 
  ascertained, 
  are 
  of 
  a 
  

   more 
  recent 
  formation, 
  and 
  lie 
  above 
  the 
  Eocene. 
  

  

  