Vol.  49.] 
ANNIVEESAEY  ADDEESS  OF  THE  PEESIDENT. 
77 
extent  supplementary  to  that  on  the  Palaeolithic  Plint-implements 
at  Ightham.  The  anthropological  questions  raised  in  this  remark¬ 
able  paper  I  do  not  venture  to  discuss,  but  there  also  the  Author 
insists  that  the  high-level  deposits  were  formed  anteriorly  to  what 
he  calls  the  post-glacial  drifts  of  the  Thames  and  Medway,  the 
deposits  on  the  Chalk-plateau  being  abruptly  cut  off  by  the  river- 
valleys. 
Shifting  the  venue  now  to  the  south  side  of  the  Weald,  com¬ 
prising  the  basins  of  the  Arun,  Adur,  Ouse,  and  Cuckmere,  we  have 
the  testimony  of  Mr.  Elsden,  who  observes  that  the  angular-flint 
drift  occurs  mainly  on  the  higher  parts  of  the  district  and  is  wanting 
in  the  river-valleys,  where  river-gravels  derived  from  the  denudation 
of  older  deposits  are  abundantly  developed.  ISTot  only  in  the 
Wealden  area,  he  continues,  but  in  many  of  the  neighbouring 
districts,  the  angular-flint  drift  consists  of  the  undenuded  remnants 
of  a  deposit  formed  before  the  present  river-valleys  were  excavated  : 
many  of  the  river-gravels,  though  newer  than  the  angular  drift,  were 
deposited  when  the  valleys  were  less  deep.  He  considered  that 
Mr.  Searles  Wood's  marine  theory  of  the  origin  of  these  gravels  was 
refuted  by  their  mode  of  occurrence. 
If  time  and  the  necessity  of  dealing  with  other  subjects  permitted, 
it  would  be  interesting  to  touch  on  some  of  the  questions  raised  by 
Prof.  Prestwich’s  last  paper  ‘  On  the  Head  or  Rubble  Drift  of  the 
South  of  England.’  There  are  also  two  papers  by  Mr.  Clement 
Reid  relating  to  the  Pleistocene  Geology  of  Sussex.  His  suggestion 
as  to  the  origin  of  Coombe  Rock  seems  very  natural.  It  is  quite 
possible  that  the  cold  in  winter  during  all  three  phases  of  the 
Glacial  epoch  may  have  been  as  severe  in  the  South  of  England  as 
in  the  most  glaciated  regions  of  the  northern  part  of  these  islands. 
Such  being  the  case,  the  ground  would  be  frozen  to  a  considerable 
depth,  and  the  drainage-system  of  the  Chalk  more  or  less  modified. 
The  summer  rains  would  run  off  any  steep  slope,  tearing  up  the 
layer  of  rubble  already  loosened  by  frost,  and  carrying  down  masses 
of  Chalk  too  rapidly  for  solvents  to  have  much  effect.  A  similar 
suggestion  with  reference  to  certain  deposits  in  connexion  with 
the  Yorkshire  Wolds  has  been  made  by  the  Rev.  E.  M.  Cole  and 
Mr.  Lamplugh.  The  submergence  shown  by  the  marine  beach  at 
Goodwood,  130  feet  above  sea-level,  is  stated  to  have  occurred  before 
the  deposit  of  Coombe  Rock.  Mr.  Reid’s  investigations,  as  narrated 
in  a  second  paper,  tended  also  to  show  that  erratics  on  the  Sussex 
coast  have,  in  some  cases,  travelled  from  the  west  or  south. 
Dorsetshire  is  the  next  county  which  claims  our  attention  in 
