﻿of 
  the 
  Northern 
  Appalachians. 
  239 
  

  

  ing 
  the 
  problem 
  this 
  study 
  appeared 
  to 
  make 
  it 
  more 
  

   complex, 
  for 
  the 
  highest 
  surface 
  to 
  the 
  north 
  did 
  not 
  

   warp 
  down 
  to 
  coincide 
  with 
  the 
  highest 
  one 
  to 
  the 
  south. 
  

   On 
  the 
  contrary, 
  it 
  disappeared 
  by 
  passing 
  out 
  above 
  the 
  

   latter 
  and 
  the 
  second 
  surface 
  to 
  the 
  north 
  became 
  coin- 
  

   cident 
  with 
  the 
  highest 
  to 
  the 
  south: 
  Furthermore, 
  the 
  

   slopes 
  of 
  none 
  of 
  these 
  could 
  be 
  correlated 
  with 
  the 
  slopes 
  

   of 
  the 
  Cretaceous 
  formations 
  or 
  the 
  older 
  peneplaned 
  

   surfaces 
  of 
  the 
  crystalline 
  rocks 
  on 
  which 
  these 
  beds 
  

   rested. 
  It 
  was 
  clear, 
  then, 
  that 
  the 
  entire 
  problem 
  of 
  the 
  

   post-Jurassic 
  history 
  of 
  the 
  northern 
  Appalachians 
  

   needed 
  re-examination. 
  

  

  Citation 
  from 
  the 
  Master 
  of 
  Science 
  thesis, 
  with 
  editorial 
  note. 
  

  

  The 
  full 
  title 
  of 
  the 
  thesis 
  referred 
  to 
  in 
  the 
  previous 
  

   section 
  is 
  as 
  follows 
  ."The 
  Geological 
  History 
  of 
  the 
  

   Archean 
  Highlands 
  of 
  New 
  Jersey, 
  including 
  their 
  exten- 
  

   sion 
  in 
  New 
  York 
  and 
  Pennsylvania, 
  1896, 
  Joseph 
  Bar- 
  

   ren.' 
  ' 
  The 
  thesis 
  is 
  divided 
  into 
  two 
  parts, 
  namely, 
  

   "Part 
  I, 
  The 
  geological 
  description 
  of 
  the 
  Highlands" 
  

   and 
  "Part 
  II, 
  The 
  geological 
  history 
  of 
  the 
  Highland 
  

   province." 
  The 
  extracts 
  here 
  given 
  are 
  from 
  Chap. 
  

   VIII, 
  Part 
  II, 
  which 
  is 
  entitled 
  "History 
  of 
  the 
  Later 
  

   Mesozoic 
  and 
  Tertiary 
  drainage." 
  These 
  extracts, 
  and 
  

   much 
  more 
  so 
  the 
  thesis 
  as 
  a 
  whole, 
  give 
  clear 
  evidence 
  

   of 
  the 
  penetration 
  of 
  thought 
  and 
  breadth 
  of 
  vision 
  which 
  

   were 
  so 
  characteristic 
  of 
  Professor 
  BarrelPs 
  work 
  in 
  

   later 
  years. 
  

  

  After 
  reviewing 
  numerous 
  facts 
  in 
  regard 
  to 
  the 
  drain- 
  

   age, 
  Barrell 
  concluded 
  that 
  "The 
  drainage 
  indicates 
  a 
  

   Mesozoic 
  burial 
  of 
  the 
  Blue 
  Eidge" 
  and 
  he 
  went 
  on 
  to 
  

   "investigate 
  the 
  causes 
  which 
  could 
  have 
  led 
  to 
  the 
  incon- 
  

   sequent, 
  discordant 
  drainage 
  of 
  the 
  minor 
  streams 
  across 
  

   the 
  Blue 
  Ridge" 
  under 
  the 
  following 
  headings: 
  "(a) 
  

   Hypothesis 
  of 
  streams 
  consequent 
  upon 
  the 
  original 
  

   structure, 
  (Not 
  adequate)"; 
  "(fr) 
  Hypothesis 
  of 
  flow 
  

   across 
  Blue 
  Ridge 
  being 
  due 
  to 
  crustal 
  tilting 
  after 
  pene- 
  

   planation, 
  (Not 
  probable)"; 
  "(c) 
  Flow 
  across 
  Blue 
  

   Ridge 
  indicates 
  burial 
  beneath 
  Mesozoic 
  sediments, 
  

   (Probable)." 
  

  

  Under 
  (c) 
  he 
  wrote: 
  "The 
  only 
  remaining 
  hypothesis 
  

   which 
  occurs 
  to 
  the 
  writer 
  to 
  account 
  for 
  this 
  anomalous 
  

   drainage 
  at 
  the 
  opening' 
  of 
  the 
  Tertiary 
  is 
  to 
  assume 
  that 
  

   previously 
  a 
  layer 
  of 
  waste 
  had 
  been 
  laid 
  down 
  over 
  the 
  

  

  