﻿222 
  History 
  of 
  Durham. 
  

  

  It 
  is 
  characterized 
  by 
  its 
  tough, 
  rich, 
  silky 
  leaf, 
  and 
  sweet 
  

   flavor, 
  due 
  to 
  the 
  soil, 
  the 
  varieties 
  cultivated 
  (Sweet 
  Ori- 
  

   noco 
  and 
  Flannagan), 
  and 
  (he 
  peculiar 
  mode 
  of 
  curing 
  by 
  

   flues, 
  both 
  walls 
  and 
  tops 
  of 
  stone, 
  and 
  slow 
  firing 
  until 
  the 
  

   leaf 
  is 
  dried. 
  

  

  VIRGINIA 
  SOILS. 
  

  

  The 
  soils 
  of 
  Virginia 
  are 
  as 
  varied 
  as 
  the 
  rocks 
  they 
  over- 
  

   lie. 
  A 
  geological 
  survey 
  of 
  the 
  State 
  was 
  made 
  by 
  Professor 
  

   William 
  B. 
  Rogers 
  in 
  the 
  3'ears 
  from 
  1835 
  to 
  1840. 
  It 
  is 
  

   necessary 
  to 
  notice 
  carefully 
  only 
  the 
  soils 
  of 
  the 
  tobacco 
  

   area. 
  

  

  The 
  Tidewater 
  Region. 
  — 
  This 
  is 
  Tertiary, 
  and 
  its 
  soils 
  are 
  

   principally 
  alluvials 
  — 
  sand 
  and 
  clay. 
  Tobacco 
  was 
  once 
  

   cultivated 
  over 
  the 
  greater 
  part 
  of 
  this 
  district, 
  but 
  it 
  has 
  

   long 
  ago 
  given 
  place 
  to 
  crops 
  more 
  suited 
  to 
  its 
  soils 
  or 
  to 
  

   the 
  choice 
  of 
  their 
  owners. 
  

  

  The 
  Middle 
  Country. 
  — 
  This 
  is 
  the 
  great 
  tobacco-producing 
  

   area 
  of 
  the 
  State, 
  bounded 
  on 
  the 
  north 
  by 
  the 
  Rappahan- 
  

   nock, 
  on 
  the 
  east 
  by 
  Tidewater, 
  on 
  the 
  south 
  by 
  North 
  

   Carolina, 
  and 
  on 
  the 
  west 
  by 
  Piedmont. 
  It 
  is 
  an 
  extended 
  

   rolling 
  plain, 
  greatly 
  diversified 
  by 
  hills 
  and 
  vales, 
  forests 
  

   and 
  streams. 
  Its 
  geology 
  is 
  primary 
  ; 
  its 
  rocks 
  azoic, 
  many 
  

   containing 
  mineral 
  elements 
  that 
  by 
  decomposing 
  greatly 
  

   enrich 
  the 
  soil, 
  such 
  as 
  granite, 
  gneiss, 
  syenite, 
  hornblende, 
  

   mica 
  schist, 
  micaceous, 
  talcose, 
  and 
  argillaceous 
  slates 
  and 
  

   shales, 
  and 
  the 
  sedimentary 
  rocks 
  of 
  the 
  Jurassic 
  and 
  Tri- 
  

   assic 
  formations. 
  The 
  soil 
  varies 
  in 
  depth 
  on 
  the 
  hills 
  and 
  

   plains 
  from 
  2 
  to 
  8 
  inches, 
  while 
  along 
  the 
  rivers 
  and 
  creeks 
  

   they 
  are 
  much 
  deeper, 
  in 
  some 
  places 
  practically 
  inexhaus- 
  

   tible. 
  The 
  usual 
  depth 
  of 
  forest 
  soils 
  is 
  from 
  4 
  to 
  5 
  inches, 
  

   with 
  a 
  subsoil 
  rich 
  in 
  mineral 
  elements. 
  The 
  tobacco 
  soils 
  

   proper 
  are 
  the 
  rich 
  bottoms 
  and 
  clay-loam 
  lots 
  for 
  shipping, 
  

   and 
  thin, 
  gray, 
  light 
  soils, 
  fertilized, 
  for 
  manufacturing. 
  

   This 
  district 
  produces 
  about 
  seven-eighths 
  of 
  the 
  tobacco 
  of 
  

   the 
  State, 
  and 
  of 
  ever}-- 
  grade 
  heretofore 
  described, 
  except 
  

   the 
  flue-cured 
  manufacturing 
  grown 
  in 
  Henry 
  and 
  adjoin- 
  

   ing 
  counties. 
  

  

  Piedmont. 
  — 
  Like 
  the 
  Middle 
  division, 
  this 
  is 
  in 
  the 
  primary 
  

   region 
  ; 
  but 
  here 
  the 
  metamorphic 
  rocks 
  differ 
  considerably 
  

   from 
  those 
  of 
  middle 
  Virginia. 
  The 
  gneiss 
  is 
  coarser 
  and 
  

   darker 
  in 
  color. 
  The 
  hornblende 
  and 
  iron 
  pyrites 
  form 
  

  

  