﻿230 
  GEOLOGY. 
  

  

  The 
  green-sands 
  of 
  New 
  Jersey, 
  from 
  being 
  similarly 
  

   applied, 
  have 
  come 
  to 
  be 
  classed 
  by 
  many 
  among 
  the 
  

   marls, 
  although, 
  when 
  pure, 
  possessing 
  no 
  calcareous 
  

   properties. 
  

  

  Shell 
  marl 
  seems 
  too 
  indefinite 
  a 
  term, 
  as 
  the 
  marls 
  of 
  

   this 
  character 
  are 
  various, 
  and 
  may 
  belong 
  either 
  to 
  the 
  

   secondary 
  or 
  tertiary 
  formations, 
  or 
  have 
  a 
  marine 
  or 
  

   fresh-water 
  origin 
  ; 
  the 
  marine 
  shell-marls 
  themselves 
  

   differing 
  essentially 
  in 
  their 
  qualities. 
  

  

  Properly 
  speaking, 
  marl 
  consists 
  of 
  calcareous 
  and 
  

   argillaceous 
  earth 
  combined 
  in 
  various 
  proportions 
  ; 
  and, 
  

   as 
  the 
  former 
  or 
  latter 
  prevails, 
  so 
  is 
  it 
  benefi.cially 
  em- 
  

   ployed 
  on 
  clays 
  or 
  sands. 
  

  

  Mr. 
  Euffin, 
  than 
  whom 
  no 
  one 
  is 
  more 
  familiar 
  with 
  

   the 
  calcareous 
  fertilizers 
  of 
  our 
  country, 
  and 
  who 
  from 
  

   his 
  close 
  and 
  extended 
  observations 
  both 
  in 
  Virginia 
  and 
  

   South 
  Carolina, 
  is 
  the 
  most 
  competent 
  authority 
  on 
  the 
  

   subject, 
  in 
  view 
  of 
  the 
  confusion 
  which 
  has 
  existed, 
  

   adopts, 
  in 
  his 
  application 
  of 
  the 
  term, 
  " 
  any 
  compound 
  

   or 
  mixture 
  of 
  earths 
  of 
  which 
  carbonate 
  of 
  lime 
  in 
  any 
  

   form 
  constitutes 
  either 
  the 
  sole 
  or 
  chief 
  value 
  as 
  manure, 
  

   and 
  is 
  in 
  such 
  large 
  jDroportion 
  as 
  to 
  be 
  of 
  important 
  

   value, 
  and 
  of 
  which 
  compound 
  the 
  mass 
  is 
  soft 
  enough 
  

   to 
  be 
  excavated 
  and 
  broken 
  down 
  with 
  ordinary 
  digging 
  

   utensils." 
  

  

  The 
  application 
  of 
  marl 
  as 
  a 
  stimulant 
  of 
  the 
  soil, 
  is 
  

   of 
  very 
  ancient 
  date, 
  the 
  use 
  of 
  it 
  being 
  mentioned 
  by 
  

   Pliny, 
  and 
  other 
  ancient 
  Latin 
  writers, 
  as 
  highly 
  benefi- 
  

   cial 
  in 
  its 
  effects; 
  and 
  clays 
  and 
  marls 
  have 
  been 
  long 
  

   and 
  extensively 
  used 
  for 
  this 
  purpose, 
  in 
  England 
  and 
  

   elsewhere. 
  

  

  In 
  the 
  United 
  States, 
  marls 
  have 
  been 
  freely 
  applied 
  

   in 
  New 
  Jersey, 
  Delaware, 
  Maryland, 
  and 
  Virginia 
  ; 
  and 
  

   more 
  recently, 
  and 
  to 
  less 
  extent, 
  in 
  South 
  Carolina 
  and 
  

   other 
  States. 
  

  

  