Yol.  49.] 
ANNIVEESAEY  ADDEESS  OF  THE  PEESIDENT. 
33 
extended  up  the  Yale  of  Clwyd  to  the  same  level ;  hut  much  of  the 
stratified  material  in  that  valley  was  remanie.”  He  spoke  of 
“  torrential  freshwater  action,  operating  during  the  melting  of  the 
ice,  as  an  important  factor  not  to  be  omitted  in  studying  valley- 
gravel.” 
One  of  the  chief  points  in  dispute  on  this  as  on  a  subsequent 
occasion,  when  Dr.  Hicks  read  a  paper  on  the  Cae  Gwyn  cave, 
referred  to  the  precise  age  of  the  bone-earth  at  the  bottom  of  that 
cave,  the  mouth  of  which  is  400  feet  above  sea-level.  Dr.  Hick 
maintained  there  was  no  foundation  for  the  view  that  the  drift, 
which  covered  up  the  entrance  and  extended  into  the  cavern,  was 
remanie.  He  claimed  that  the  deposits  which  lay  over  the  bone-earth 
were  in  situ  and  were  identical  with  the  normal  Glacial  deposits  of 
the  area,  and  that  the  cavern  had  been  completely  buried  in  them. 
These  drifts  Mr.  Strahan  believed  were  part  of  the  Northern  Drift 
which  he  had  mapped  over  a  large  portion  of  Denbighshire,  Flint¬ 
shire,  and  Cheshire.  On  the  whole,  it  must  be  admitted  that  the 
testimony  of  the  majority  of  geologists  was  in  favour  of  the  view 
that  this  bone-earth,  with  its  peculiar  fauna,  so  different  from  that 
of  the  post-Glacial  fauna  of  the  vicinity  (Morton),  and  bearing  a 
certain  resemblance  to  the  Forest-bed  fauna,  has  been  sealed  up  by  a 
Drift,  which  is  most  probably  that  derived  from  the  Irish  Sea,  and 
which,  if  we  accept  its  glacial  origin,  represents  in  all  probability 
the  most  severe  period  of  the  Great  Ice  Age.  How  much  older  the 
bone-earth  may  be  than  this  Drift  it  is  not  easy  to  say,  but  appear¬ 
ances  are  certainly  in  favour  of  its  being  early  Glacial.  The  point 
is  one  of  considerable  interest,  because  of  the  associated  Palaeolithic 
implements ;  but  into  this  part  of  the  controversy  I  do  not  venture 
to  enter. 
The  question  of  the  glacial  origin  of  the  Drift  of  the  Irish  Sea  is 
one  of  more  importance  from  a  geological  point  of  view,  and  it  bears 
also  on  some  of  the  points  brought  forwards  in  the  Cae  Gwyn  dis¬ 
cussion.  It  was  alleged,  for  instance,  that  the  sea  during  the  great 
submergence  would  have  washed  all  the  bone-earth  and  its  contents 
out  of  the  cave,  on  the  supposition  that  those  contents  were  of  early 
Glacial  age.  But  if  the  sea  never  reached  the  mouth  of  the  cavern, 
as  the  opponents  of  the  Great  Submergence  hypothesis  might 
allege,  this  difficulty  at  once  disappears. 
In  this  connexion  there  is  a  paper  by  Mr.  A.  C.  Nicholson,  ‘  On  the 
high-level  Glacial  Gravels  at  Gloppa,  near  Oswestry/  which  raises 
the  same  questions  that  have  been  so  often  discussed  with  reference 
