﻿11] 
  General 
  Geoi^ogy 
  : 
  Quaternary 
  107 
  

  

  too 
  meagre 
  to 
  justify 
  such 
  a 
  statement. 
  But 
  it 
  is 
  felt 
  that 
  as 
  

   the 
  stratigraphy 
  of 
  the 
  Southern 
  states 
  is 
  more 
  carefully 
  worked 
  

   out 
  the 
  positions 
  of 
  some 
  of 
  the 
  gravel 
  beds, 
  which 
  now 
  seem 
  

   very 
  strange 
  will 
  become 
  quite 
  clear, 
  and 
  that 
  parts 
  of 
  them 
  will 
  

   be 
  found 
  to 
  be 
  the 
  true 
  equivalents 
  of 
  adjoining 
  fossiliferous 
  beds. 
  

  

  QUATERNARY 
  

  

  Classification 
  

   Historical 
  

  

  The 
  literature 
  on 
  the 
  Quaternary 
  deposits 
  of 
  L,ouisiana 
  is 
  quite 
  

   voluminous. 
  The 
  great 
  river 
  and 
  its 
  delta 
  have 
  been 
  studied 
  

   and 
  written 
  about 
  since 
  the 
  first 
  settlement 
  of 
  the 
  country. 
  

   Commerce 
  demanded 
  it 
  ; 
  and 
  the 
  scientific 
  man 
  found 
  in 
  the 
  river 
  

   and 
  flood 
  plain, 
  problems 
  of 
  very 
  great 
  interest. 
  Some 
  of 
  these 
  

   problems 
  are 
  so 
  large 
  and 
  the 
  observed 
  data 
  so 
  small 
  that 
  our 
  

   present 
  knowledge 
  is 
  by 
  no 
  means 
  satisfactory. 
  Their 
  elucida- 
  

   tion 
  will 
  require 
  some 
  years 
  of 
  very 
  careful 
  hard 
  work. 
  

  

  Lyell. 
  — 
  Passing 
  over 
  the 
  early 
  observations 
  of 
  the 
  U. 
  S. 
  

   Engineers 
  engaged 
  in 
  work 
  on 
  the 
  river 
  and 
  of 
  the 
  earlier 
  

   unpublished 
  part 
  of 
  the 
  work 
  of 
  Forshey 
  and 
  Riddel 
  we 
  come 
  to 
  

   Sir 
  Charles 
  Lyell. 
  The 
  visit 
  of 
  this 
  great 
  geologist, 
  and 
  his 
  

   subsequent 
  publications 
  may 
  be 
  considered 
  the 
  beginning 
  of 
  

   the 
  present 
  study 
  of 
  the 
  river 
  deposits. 
  He 
  conceived 
  for 
  the 
  

   alluvial 
  deposits 
  a 
  thickness 
  of 
  at 
  least 
  500 
  feet 
  and 
  on 
  this 
  based 
  

   his 
  calculation 
  of 
  67,000 
  years 
  as 
  the 
  age 
  of 
  the 
  delta. 
  He 
  

   recognized 
  the 
  loess, 
  and 
  at 
  Port 
  Hudson 
  saw 
  deposits 
  which 
  he 
  

   considered 
  to 
  be 
  of 
  alluvial 
  formation.* 
  

  

  Hi/gard.— 
  lnh\s 
  Mississippi 
  Report, 
  i860, 
  Hilgard 
  proposed 
  

   the 
  name 
  Coast 
  Pliocene 
  for 
  a 
  series 
  of 
  recent, 
  partly 
  cypress 
  

   swamp, 
  partly 
  marine 
  beds 
  with 
  recent 
  shells, 
  occupying 
  a 
  strip 
  

   along 
  the 
  Gulf 
  Coast 
  from 
  12 
  to 
  20 
  miles 
  wide. 
  This 
  has 
  its 
  

   homologue 
  along 
  the 
  whole 
  southern 
  coast 
  of 
  Louisiana. 
  In 
  

   the 
  same 
  report 
  he 
  recognized 
  and 
  named 
  the 
  Yellow 
  Ivoam.f 
  

  

  * 
  Second 
  visit 
  to 
  the 
  United 
  States, 
  3d 
  Ed., 
  1855, 
  p. 
  250 
  ; 
  also 
  Principles 
  

   of 
  Geology, 
  nth 
  Ed., 
  p. 
  455. 
  

  

  f 
  Report 
  on 
  the 
  Geology 
  and 
  Agriculture 
  of 
  the 
  State 
  of 
  Mississippi, 
  

   i860, 
  p. 
  197. 
  

  

  