﻿12 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  [Nov. 
  4, 
  

  

  a 
  mile 
  from 
  the 
  river, 
  and 
  the 
  surface 
  of 
  its 
  alluvial 
  banks 
  some 
  50 
  

   to 
  60 
  feet 
  above 
  the 
  modern 
  level 
  of 
  high 
  water. 
  

  

  Syenite 
  is 
  the 
  chief 
  rock 
  at 
  the 
  Second 
  Cataract. 
  Like 
  the 
  Cata- 
  

   ract 
  of 
  Assuan, 
  the 
  waters 
  flow 
  placidly 
  for 
  some 
  distance 
  through 
  

   the 
  rocky 
  barrier 
  to 
  a 
  ridge 
  of 
  granite, 
  through 
  which 
  they 
  burst 
  with 
  

   great 
  force 
  and 
  considerable 
  noise. 
  Afterwards 
  the 
  waters 
  disperse 
  

   in 
  numberless 
  rock-channels, 
  where 
  the 
  velocity 
  is 
  gradually 
  lost, 
  to 
  

   again 
  unite 
  and 
  form 
  the 
  steady 
  slow 
  river 
  which 
  flows 
  on 
  at 
  a 
  uni- 
  

   form 
  rate 
  until 
  it 
  is 
  again 
  sent 
  dashing 
  through 
  the 
  granitic 
  rocks 
  

   of 
  the 
  First 
  Cataract, 
  when 
  all 
  its 
  troubles 
  cease, 
  and 
  hence 
  to 
  the 
  

   Mediterranean 
  scarcely 
  a 
  ripple 
  disturbs 
  its 
  even 
  surface. 
  At 
  the 
  

   termination 
  of 
  the 
  Second 
  Cataract 
  or 
  Rapid, 
  a 
  short 
  way 
  above 
  

   Wadi 
  Halfeh, 
  the 
  last 
  pinnacle 
  of 
  syenite 
  is 
  seen 
  jutting 
  up, 
  with 
  a 
  

   sand-bank 
  forming 
  the 
  usual 
  " 
  crag 
  and 
  tail," 
  which 
  on 
  a 
  larger 
  

   scale 
  have 
  produced 
  the 
  Island 
  of 
  Phike 
  above, 
  and 
  that 
  of 
  Elephan- 
  

   tine 
  below, 
  the 
  Cataract 
  of 
  Assuan. 
  

  

  6. 
  Freshwater 
  Shells 
  on 
  the 
  Terraces. 
  — 
  An 
  examination 
  of 
  the 
  

   older 
  rocks 
  of 
  the 
  Second 
  Cataract 
  shows 
  former 
  levels 
  of 
  the 
  river, 
  

   more 
  especially 
  on 
  the 
  left 
  bank, 
  south 
  of 
  the 
  sandstone-cliff 
  at 
  

   Abusir, 
  around 
  the 
  base 
  of 
  which 
  the 
  river 
  is 
  now 
  excavating, 
  as 
  is 
  

   evident 
  from 
  the 
  masses 
  of 
  rock 
  which 
  have 
  fallen 
  down. 
  On 
  the 
  

   above-named 
  levels 
  and 
  for 
  a 
  long 
  way 
  southward, 
  and 
  upwards 
  of 
  

   a 
  mile 
  inland, 
  I 
  noticed 
  abundance 
  of 
  river-shells* 
  (Unio 
  pictorum, 
  

   U. 
  lithophagus, 
  and 
  Paludina 
  bulimoides) 
  strewn 
  over 
  the 
  surface 
  of 
  

   the 
  sands. 
  On 
  the 
  right 
  bank 
  of 
  the 
  river 
  there 
  are 
  indications 
  of 
  

   old 
  channels, 
  perhaps 
  better 
  marked 
  than 
  those 
  noticed 
  on 
  the 
  left. 
  

   I 
  did 
  not, 
  however, 
  examine 
  that 
  locality, 
  and 
  the 
  Shells 
  found 
  in 
  

   the 
  above 
  situation 
  did 
  not 
  then, 
  as 
  afterwards, 
  attract 
  my 
  atten- 
  

   tion 
  to 
  seek 
  for 
  them 
  among 
  the 
  soil 
  underneath 
  the 
  sand-drift, 
  

   whence, 
  I 
  have 
  now 
  no 
  doubt, 
  they 
  were 
  washed. 
  At 
  Derr, 
  the 
  capital 
  

   of 
  Nubia 
  (eighty 
  miles 
  north 
  of 
  the 
  Second 
  Cataract), 
  the 
  cultivated 
  

   tract 
  of 
  alluvium 
  extends 
  from 
  the 
  river 
  eastward 
  about 
  600 
  or 
  

   700 
  yards, 
  until 
  bounded 
  by 
  a 
  rough 
  and 
  steep 
  face 
  of 
  sandstone, 
  40 
  

   to 
  50 
  feet 
  in 
  height, 
  in 
  which 
  is 
  excavated 
  a 
  temple 
  of 
  the 
  time 
  of 
  

   Rameses 
  the 
  Great, 
  about 
  b.c 
  1355. 
  On 
  the 
  top 
  is 
  a 
  level 
  plain, 
  

   extending 
  north 
  and 
  south, 
  and 
  gradually 
  rising 
  eastward, 
  towards 
  

   a 
  bare 
  range 
  of 
  conical 
  hills. 
  The 
  surface 
  of 
  this 
  plateau 
  is 
  very 
  

   stony, 
  and, 
  as 
  usual, 
  is 
  covered 
  with 
  angular 
  fragments 
  of 
  hard 
  

   sandstone 
  and 
  rounded 
  pebbles 
  from 
  the 
  grit, 
  and 
  coarser 
  varieties 
  

   of 
  that 
  rock. 
  Under 
  these 
  occurs 
  a 
  scanty 
  reddish-brown 
  soil, 
  con- 
  

   taining 
  natron, 
  which 
  the 
  natives 
  use 
  as 
  a 
  top-dressing 
  for 
  their 
  

   fields. 
  In 
  the 
  excavations, 
  and 
  throughout 
  this 
  soil, 
  I 
  found 
  abun- 
  

   dance 
  of 
  Cyrena 
  jluminalisf, 
  a 
  species 
  identical 
  with 
  the 
  common 
  

   Shell 
  of 
  the 
  Nile. 
  It 
  occurred 
  in 
  great 
  numbers 
  from 
  the 
  margin 
  of 
  

   the 
  plateau, 
  immediately 
  above 
  the 
  temple, 
  eastward 
  for 
  upwards 
  of 
  

   a 
  mile 
  and 
  a 
  half. 
  The 
  height 
  of 
  this 
  flat 
  land 
  varies, 
  according 
  to 
  

   our 
  estimations, 
  from 
  130 
  to 
  110 
  feet 
  above 
  the 
  highest 
  mark 
  of 
  the 
  

   Nile's 
  inundation 
  in 
  the 
  present 
  day. 
  The 
  following 
  sketch 
  will 
  

  

  * 
  See 
  Specimens 
  Nos. 
  1 
  and 
  2. 
  + 
  See 
  Specimen 
  No. 
  3. 
  

  

  