﻿442 
  DR. 
  H. 
  HICKS 
  ON 
  THE 
  MORTE 
  SLATES, 
  AND 
  [Aug. 
  1897,- 
  

  

  III. 
  The 
  Brendon 
  Hills. 
  

  

  In 
  following 
  the 
  section 
  southward 
  from 
  Treborough 
  Quarry, 
  

   there 
  appears 
  to 
  be 
  very 
  little 
  change 
  in 
  the 
  character 
  of 
  the 
  

   deposits 
  until 
  we 
  reach 
  Treborough 
  Common, 
  and 
  the 
  dip 
  is 
  every- 
  

   where 
  at 
  a 
  high 
  angle. 
  Here, 
  however, 
  the 
  beds 
  are 
  more 
  sandy 
  

   and 
  flag-like 
  in 
  character, 
  but 
  often 
  much 
  crushed. 
  The 
  change 
  is 
  

   so 
  marked 
  that 
  I 
  have 
  classed 
  them 
  under 
  the 
  name 
  of 
  Brendon 
  

   Hill 
  Series. 
  At 
  some 
  points 
  they 
  could 
  easily, 
  from 
  their 
  mineral 
  

   character, 
  be 
  classed 
  with 
  some 
  of 
  the 
  Hangman 
  or 
  Pickwell 
  Down 
  

   Beds 
  ; 
  and 
  beds 
  of 
  like 
  appearance 
  farther 
  west 
  have 
  been 
  coloured 
  

   by 
  Mr. 
  Ussher 
  on 
  his 
  map 
  as 
  Pickwell 
  Down 
  Beds, 
  thrust 
  in 
  by 
  

   faults 
  among, 
  or 
  reposing 
  upon, 
  the 
  Morte 
  Slates. 
  They 
  occupy 
  

   an 
  area 
  of 
  more 
  than 
  a 
  mile 
  in 
  width, 
  and 
  the 
  Brendon 
  Hill 
  mines 
  

   of 
  iron-ore 
  occur 
  in 
  them. 
  The 
  evidence 
  would 
  lead 
  one 
  to 
  suspect 
  

   that 
  some 
  at 
  least 
  of 
  these 
  beds 
  are 
  much 
  newer 
  than 
  the 
  Tre- 
  

   borough 
  or 
  Oakhampton 
  Slates, 
  and 
  that 
  they 
  occur 
  here 
  as 
  the 
  

   result 
  of 
  faults, 
  in 
  a 
  crushed 
  and 
  broken 
  condition, 
  among 
  the 
  

   older 
  rocks. 
  They 
  extend 
  evidently 
  for 
  a 
  considerable 
  distance 
  in 
  an 
  

   east-and-west 
  direction, 
  and 
  form 
  the 
  highest 
  ground 
  in 
  the 
  area. 
  

   South 
  of 
  the 
  Brendon 
  Hills 
  slates 
  are 
  again 
  found 
  on 
  the 
  surface, 
  

   the 
  beds 
  dip 
  at 
  a 
  high 
  angle, 
  and 
  are 
  repeated 
  in 
  numerous 
  folds 
  

   until 
  we 
  reach 
  the 
  neighbourhood 
  of 
  the 
  Oakhampton 
  and 
  Combe 
  

   slate-quarries. 
  

  

  IV. 
  The 
  Wiveliscombe 
  District. 
  

  

  The 
  slates 
  of 
  the 
  Oakhampton 
  and 
  Combe 
  quarries 
  north 
  of 
  

   Wiveliscombe 
  have 
  been 
  universally 
  classed 
  with 
  the 
  Morte 
  Slates 
  

   of 
  North 
  Devon, 
  and 
  Mr. 
  Ethe 
  ridge 
  refers 
  to 
  them 
  in 
  the 
  following 
  

   words 
  (Quart. 
  Journ. 
  Geol. 
  Soc. 
  vol. 
  xxiii. 
  1867, 
  p. 
  592) 
  : 
  — 
  ' 
  From 
  

   Hawkham 
  through 
  the 
  Oakhampton 
  House 
  Quarries, 
  Whitfield, 
  etc.,. 
  

   we 
  are 
  unmistakably 
  in 
  the 
  grey 
  fissile 
  slates 
  of 
  Mortehoe 
  and 
  

   Morte 
  Bay, 
  which 
  here 
  dip 
  south 
  from 
  65° 
  to 
  70°, 
  with 
  cleavage 
  

   coincident, 
  but 
  in 
  some 
  places 
  nearly 
  vertical 
  ; 
  the 
  same 
  system 
  

   of 
  quartz-veins 
  that 
  occurs 
  at 
  Lee, 
  Mortehoe, 
  and 
  Woolacombe 
  

   occurs 
  here 
  — 
  a 
  circumstance, 
  connected 
  with 
  other 
  features, 
  tending 
  

   to 
  clearly 
  identify 
  their 
  position 
  below 
  the 
  range 
  of 
  the 
  Upper 
  Old 
  

   Red 
  Sandstone 
  before 
  mentioned.' 
  Mr. 
  Etheridge 
  makes 
  the 
  slates 
  

   pass 
  conformably 
  under 
  the 
  Pickwell 
  Down 
  Sandstones 
  of 
  Maun- 
  

   down 
  ; 
  but 
  Sir 
  H. 
  De 
  la 
  Beche 
  and 
  Prof. 
  Jukes 
  inserted 
  a 
  fault 
  

   between 
  the 
  two 
  series, 
  and 
  indicated 
  it 
  as 
  passing 
  in 
  an 
  east-and- 
  

   west 
  direction 
  through 
  Langley 
  Marsh. 
  It 
  seems 
  to 
  me 
  that 
  there 
  

   is 
  undoubtedly 
  a 
  well-marked 
  fault 
  here, 
  and 
  the 
  beds 
  are 
  much 
  

   crushed 
  in 
  the 
  valley 
  which 
  intervenes 
  between 
  the 
  sandstones 
  on 
  

   the 
  south 
  and 
  the 
  slates 
  on 
  the 
  north 
  side. 
  Prof. 
  Jukes, 
  however, 
  

   instead 
  of 
  placing 
  the 
  slates 
  on 
  a 
  lower 
  horizon 
  than 
  the 
  sandstones,, 
  

   supposed 
  that 
  the 
  latter, 
  which 
  he 
  called 
  Old 
  Bed 
  Sandstones, 
  

   passed 
  under 
  the 
  slates, 
  which 
  he 
  classed 
  as 
  Carboniferous 
  Slates. 
  

   In 
  this 
  he 
  was 
  entirely 
  mistaken, 
  as 
  the 
  slates 
  are 
  now 
  known 
  to- 
  

   contain 
  Lower 
  Devonian 
  fossils. 
  No 
  fossils 
  had 
  been 
  found 
  in 
  the* 
  

  

  