﻿346 
  ME. 
  T. 
  MELLAKD 
  READE 
  ON 
  THE 
  [Aug. 
  1 
  897, 
  

  

  gravelly 
  sand 
  that 
  runs 
  loosely 
  down 
  the 
  flanks 
  of 
  the 
  excavated 
  

   portion 
  were 
  marine 
  shell-fragments 
  of 
  the 
  usual 
  type. 
  

  

  The 
  pebbles 
  are 
  preponderatingly 
  of 
  Carboniferous 
  Limestone. 
  

   There 
  are 
  too 
  a 
  great 
  many 
  boulders 
  of 
  the 
  same 
  rock 
  lj 
  ing 
  about 
  

   that 
  have 
  been 
  taken 
  out 
  of 
  the 
  mound. 
  Boulders 
  and 
  pebbles 
  of 
  a 
  

   fine-grained 
  felstone 
  also 
  abound, 
  and 
  these 
  may 
  have 
  come 
  from 
  

   the 
  Snowdon 
  range. 
  There 
  are, 
  moreover, 
  other 
  rocks 
  which 
  both 
  

   Mr. 
  Ruddy 
  and 
  I 
  consider 
  to 
  be 
  from 
  the 
  Arenig. 
  

  

  At 
  A 
  (see 
  diagram, 
  p. 
  345) 
  I 
  took 
  a 
  specimen 
  of 
  the 
  sand 
  and 
  

   gravel, 
  at 
  a 
  level 
  of 
  about 
  350 
  feet 
  above 
  O.D. 
  The 
  result 
  of 
  

   mechanical 
  analysis 
  was 
  as 
  follows: 
  — 
  

  

  Weight 
  before 
  washing 
  = 
  5 
  oz. 
  = 
  TOOO. 
  

  

  Caught 
  in 
  ^V-moh 
  mesh 
  O700 
  

  

  A 
  „ 
  0083 
  

  

  T 
  ho 
  „ 
  0-100 
  

  

  Passed 
  T 
  J^ 
  „ 
  - 
  050 
  

  

  Clay? 
  = 
  7 
  per 
  cent. 
  0-933 
  

  

  The 
  -gL-inch 
  material 
  contained 
  some 
  extremely 
  rounded 
  and 
  

   beautifully 
  polished 
  pebbles, 
  measuring 
  from 
  | 
  inch 
  on 
  the 
  longer 
  

   axis 
  down 
  to 
  ^ 
  inch, 
  of 
  very 
  hard, 
  green, 
  igneous 
  rock 
  ; 
  there 
  were 
  

   also 
  pebbles 
  of 
  limestone, 
  sandstone, 
  vein-quartz, 
  and 
  a 
  few 
  shell- 
  

   fragments. 
  None 
  of 
  this 
  material 
  was 
  striated, 
  but 
  it 
  had 
  a 
  beach- 
  

   worn 
  appearance. 
  

  

  The 
  material 
  from 
  the 
  smaller 
  meshes 
  consisted, 
  as 
  is 
  generally 
  

   the 
  case, 
  of 
  a 
  larger 
  proportion 
  of 
  quartz-grains 
  as 
  the 
  material 
  

   became 
  smaller. 
  Many 
  of 
  them 
  were 
  rounded 
  and 
  polished, 
  but 
  

   mixed 
  with 
  irregular 
  quartz 
  -splinters. 
  The 
  material 
  is 
  largely 
  

   calcareous, 
  as 
  shown 
  by 
  its 
  bubbling 
  up 
  strongly 
  on 
  the 
  application 
  

   of 
  acid. 
  

  

  The 
  Boulder 
  Clay 
  on 
  the 
  flanks 
  of 
  the 
  mound, 
  although 
  it 
  was 
  

   seen 
  on 
  the 
  ground 
  to 
  contain 
  small 
  shell-fragments, 
  did 
  not 
  yield 
  

   foraminifera 
  to 
  Mr. 
  Wright, 
  who 
  examined 
  a 
  specimen 
  from 
  B 
  (see 
  

   diagram, 
  p. 
  345). 
  The 
  stones, 
  he 
  reports, 
  were 
  more 
  or 
  less 
  rounded. 
  

  

  The 
  Boulder 
  Clay 
  appears 
  to 
  cover 
  the 
  surrounding 
  country, 
  

   being 
  seen 
  in 
  the 
  cutting 
  of 
  the 
  Prestatyn 
  Branch 
  Railway, 
  ac- 
  

   cording 
  to 
  Mr. 
  Strahan, 
  so 
  that 
  the 
  gravel-mound 
  must 
  rise 
  up 
  

   through 
  it. 
  On 
  the 
  road 
  to 
  Newmarket, 
  at 
  a 
  level 
  of 
  about 
  500 
  feet, 
  

   a 
  sand-pit 
  (No. 
  6 
  in 
  the 
  Map) 
  shows 
  yellow 
  stratified 
  sand, 
  with 
  

   frequent 
  shell-fragments. 
  

  

  These 
  flanking 
  deposits 
  on 
  either 
  side 
  of 
  the 
  Vale 
  of 
  Clwyd 
  

   bear 
  all 
  the 
  appearance 
  of 
  marine 
  clays 
  and 
  sands, 
  ami 
  are, 
  as 
  I 
  

   have 
  shown 
  in 
  detail, 
  full 
  of 
  the 
  remains 
  of 
  marine 
  organisms. 
  

   Similar 
  deposits, 
  in 
  this 
  case 
  consisting 
  mainly 
  of 
  the 
  red 
  sand 
  

   of 
  the 
  Vale 
  of 
  Clwyd, 
  can 
  be 
  traced 
  up 
  the 
  River 
  Wheeler 
  into 
  

   the 
  valley 
  of 
  the 
  Alyn 
  and 
  down 
  to 
  its 
  junction 
  with 
  the 
  Dee. 
  

   Farther 
  up 
  the 
  Vale 
  of 
  Clwyd 
  this 
  marine 
  drift 
  gives 
  place 
  to 
  a 
  

   more 
  local 
  drift, 
  which 
  has 
  come, 
  as 
  shown 
  by 
  Mr. 
  Strahan, 
  from 
  

  

  