﻿PALEOLITHIC 
  FLINT 
  IMPLEMENTS 
  IN 
  KENT. 
  277 
  

  

  60 
  feet 
  that 
  of 
  the 
  present 
  stream 
  at 
  Ightham, 
  though 
  this 
  may 
  

   have 
  been 
  increased 
  lower 
  down 
  the 
  valley 
  by 
  the 
  greater 
  fall 
  at 
  

   its 
  outlet, 
  caused 
  by 
  the 
  more 
  rapid 
  denudation 
  of 
  the 
  Medway 
  

   valley. 
  We 
  have 
  therefore 
  only 
  to 
  look 
  to 
  the 
  drift-beds 
  below 
  the 
  

   contour-level 
  of 
  350 
  feet 
  or 
  thereabouts 
  in 
  the 
  upper 
  part 
  of 
  the 
  

   valley, 
  and 
  of 
  300 
  feet 
  or 
  less 
  in 
  the 
  lower 
  part, 
  where 
  the 
  valley 
  

   is 
  excavated 
  to 
  the 
  depth 
  of 
  140 
  feet 
  (figs. 
  1-4, 
  p. 
  272). 
  

  

  The 
  tributary 
  stream 
  which 
  passes 
  by 
  Ightham 
  and 
  rises 
  on 
  the 
  

   slopes 
  of 
  Oldbury 
  Hill 
  must 
  have 
  at 
  some 
  time 
  been 
  one 
  of 
  con- 
  

   siderable 
  power 
  ; 
  for 
  its 
  old 
  bed 
  above 
  Ightham 
  is, 
  I 
  am 
  informed 
  by 
  

   Mr. 
  Harrison, 
  marked 
  by 
  a 
  line 
  of 
  large 
  blocks 
  of 
  the 
  Oldbury 
  

   Stone 
  * 
  which 
  were 
  exposed 
  when 
  the 
  railway 
  was 
  being 
  made. 
  At 
  

   Pane 
  Hill, 
  higher 
  on 
  the 
  slope 
  of 
  Oldbury, 
  the 
  drift 
  belongs 
  in 
  part 
  

   to 
  the 
  Shode, 
  as 
  it 
  does 
  at 
  Bayshaw, 
  where 
  it 
  forms 
  a 
  bed 
  of 
  gravel 
  

   4 
  feet 
  thick. 
  Coney 
  Pi 
  eld 
  is 
  covered 
  by 
  a 
  white 
  flint-gravel, 
  which 
  

   may 
  also 
  be 
  of 
  this 
  age. 
  

  

  The 
  slight 
  sprinkling 
  of 
  drift 
  on 
  the 
  low 
  hills, 
  bordering 
  the 
  

   other 
  and 
  main 
  stream 
  above 
  Ightham, 
  may 
  possibly 
  be 
  a 
  river- 
  

   drift. 
  Half 
  a 
  mile 
  east 
  of 
  Ightham, 
  at 
  a 
  spot 
  called 
  Highfield, 
  

   just 
  below 
  the 
  junction 
  of 
  the 
  two 
  main 
  streams, 
  there 
  is 
  a 
  well- 
  

   marked 
  deposit 
  of 
  uudoubted 
  river-drift. 
  It 
  caps 
  a 
  hill 
  rising 
  from 
  

   50 
  to 
  60 
  feet 
  above 
  the 
  Shode. 
  The 
  gravel 
  is 
  not 
  worked 
  • 
  but 
  a 
  hole 
  

   was 
  dug, 
  which 
  showed 
  it 
  to 
  be 
  not 
  less 
  than 
  8 
  feet 
  thick, 
  roughly 
  

   stratified, 
  and 
  composed 
  approximately 
  of 
  : 
  — 
  

  

  Subangular 
  white 
  flints 
  (some 
  of 
  them 
  pitted), 
  together 
  

   with 
  a 
  few 
  others, 
  much 
  worn 
  and 
  deeply 
  stained 
  

   brown 
  about 
  50 
  per 
  cent. 
  

  

  Lower- 
  G-reensand 
  debris, 
  consisting 
  of 
  subangular 
  rag- 
  

   stone, 
  chert, 
  grit, 
  ironstone, 
  and 
  Oldbury 
  Stone 
  45 
  „ 
  

  

  Tertiary 
  flint-pebbles 
  5 
  „ 
  

  

  100 
  

   in 
  an 
  ochreous 
  sand 
  ; 
  no 
  fossils 
  were 
  found. 
  

  

  In 
  the 
  valley 
  a 
  short 
  distance 
  below, 
  and 
  at 
  a 
  level 
  of 
  a 
  few 
  feet 
  

   above 
  the 
  stream 
  f, 
  a 
  well-marked 
  bed 
  of 
  low-level 
  gravel 
  is 
  ex- 
  

   posed 
  near 
  the 
  Mills 
  at 
  Basted. 
  It 
  is 
  6 
  feet 
  thick, 
  but 
  is 
  not 
  worked, 
  

   and 
  consists 
  chiefly 
  of 
  chert 
  debris, 
  with 
  a 
  number 
  of 
  blocks 
  of 
  

   Oldbury 
  Stone, 
  and 
  a 
  certain 
  proportion 
  of 
  flints 
  and 
  flint-pebbles. 
  

  

  How 
  much 
  of 
  the 
  scattering 
  of 
  subangular 
  flints, 
  chert, 
  and 
  

   Tertiary 
  pebbles 
  at 
  Claygate 
  and 
  the 
  opposite 
  Bewley 
  slopes 
  is 
  to 
  be 
  

   assigned 
  to 
  a 
  high-level 
  river-drift, 
  is, 
  in 
  the 
  absence 
  of 
  sections, 
  

   impossible 
  to 
  say. 
  At 
  Dunks 
  Green, 
  however, 
  south 
  of 
  Plaxtol, 
  and 
  

   extending 
  thence 
  to 
  New 
  Parm, 
  Shipborne, 
  there 
  is 
  a 
  well-defined 
  

  

  * 
  The 
  Oldbury 
  Stone 
  is 
  a 
  peculiar 
  waxy 
  chert, 
  slightly 
  translucent, 
  of 
  yellow, 
  

   red, 
  and 
  grass-green 
  colours, 
  largely 
  developed 
  in 
  the 
  Folkestone 
  Beds 
  of 
  the 
  

   Lower 
  G-reensand 
  at 
  Oldbury 
  Hill 
  — 
  a 
  high 
  hill 
  (620 
  feet) 
  west 
  of 
  Ightham, 
  

   and 
  at 
  others 
  adjacent. 
  This 
  chert, 
  which 
  is 
  peculiar 
  to 
  this 
  district, 
  is 
  easily 
  

   recognized 
  in 
  the 
  drift-beds. 
  Mr. 
  Trimmer 
  found 
  it 
  on 
  Dartford 
  Heath, 
  and 
  I 
  

   have 
  found 
  it 
  in 
  various 
  parts 
  of 
  the 
  Lower-Thames 
  valley. 
  It 
  has 
  been 
  described 
  

   by 
  Prof. 
  Bonney 
  in 
  Geol. 
  Mag. 
  dec. 
  3, 
  vol. 
  v. 
  p. 
  297. 
  

  

  t 
  The 
  base 
  of 
  the 
  valley, 
  wherever 
  exposed 
  or 
  cut 
  through 
  by 
  the 
  stream, 
  

   shows 
  a 
  bed 
  of 
  gravel 
  under 
  a 
  thin 
  alluvial 
  deposit. 
  

  

  