﻿Vol. 
  53.] 
  OF 
  AUGUST 
  1892 
  AND 
  NOVEMBER 
  1 
  893. 
  165 
  

  

  entirely. 
  Though 
  preferring 
  the 
  former, 
  I 
  am 
  unable 
  to 
  decide 
  

   between 
  these 
  two 
  explanations 
  ; 
  but, 
  at 
  any 
  rate, 
  there 
  seems 
  to 
  

   be 
  no 
  reason 
  for 
  supposing 
  that 
  the 
  sound-vibrations 
  and 
  the 
  larger 
  

   vibrations 
  travelled 
  with 
  different 
  velocities. 
  

  

  Sea-Waves 
  and 
  Miscellaneous 
  Phenomena. 
  — 
  The 
  shock 
  was 
  felt 
  

   by 
  several 
  persons 
  in 
  boats, 
  the 
  sensation 
  being 
  the 
  usual 
  one 
  of 
  

   having 
  struck 
  upon 
  a 
  rock. 
  At 
  Bulwell, 
  on 
  the 
  southern 
  shore 
  of 
  

   Milford 
  Haven, 
  two 
  or 
  three 
  waves 
  were 
  seen 
  to 
  dash 
  up 
  the 
  shore, 
  

   the 
  sea 
  both 
  before 
  and 
  after 
  being 
  absolutely 
  still. 
  The 
  shock 
  was 
  

   also 
  felt 
  by 
  the 
  engineer 
  of 
  a 
  steamboat 
  on 
  the 
  river 
  opposite 
  

   Langwm. 
  'The 
  water, 
  although 
  perfectly 
  calm 
  before, 
  became 
  

   suddenly 
  swelled 
  as 
  with 
  a 
  heavy 
  breeze. 
  The 
  boat 
  seemed 
  as 
  if 
  

   passing 
  over 
  a 
  swell, 
  and 
  then 
  another, 
  and 
  then 
  another 
  — 
  three 
  

   distinct 
  waves, 
  after 
  which 
  the 
  water 
  was 
  troubled 
  for 
  a 
  few 
  

   seconds 
  : 
  then 
  it 
  became 
  perfectly 
  calm 
  as 
  before.' 
  The 
  waves 
  

   lasted 
  from 
  15 
  to 
  20 
  seconds, 
  and 
  crossed 
  the 
  river 
  from 
  north-west 
  

   to 
  south-east. 
  1 
  

  

  Some 
  hours 
  after 
  the 
  earthquake, 
  one 
  or 
  more 
  so-called 
  tidal 
  

   waves 
  were 
  observed 
  at 
  various 
  places 
  along 
  the 
  shore 
  of 
  the 
  English 
  

   Channel, 
  and 
  were 
  generally 
  regarded 
  as 
  an 
  effect 
  of 
  the 
  earth- 
  

   quake. 
  The 
  places 
  from 
  which 
  I 
  have 
  obtained 
  accounts 
  of 
  such 
  

   waves 
  are 
  (from 
  west 
  to 
  east): 
  Scilly 
  Isles, 
  Porthpean 
  (near 
  St. 
  

   Austell), 
  Lostwithiel, 
  Eiver 
  Yealm, 
  River 
  Dart, 
  estuary 
  of 
  the 
  Exe 
  

   at 
  Exmouth 
  and 
  Topsham, 
  Weymouth, 
  Portsmouth, 
  and 
  Bosham 
  (in 
  

   Sussex). 
  It 
  is 
  unnecessary 
  to 
  enter 
  into 
  any 
  detailed 
  description 
  of 
  

   the 
  waves, 
  since, 
  whatever 
  their 
  origin 
  may 
  have 
  been, 
  it 
  is 
  difficult 
  

   for 
  the 
  following 
  reasons 
  to 
  connect 
  them 
  with 
  the 
  Pembroke 
  earth- 
  

   quake 
  : 
  — 
  (1) 
  All 
  the 
  places 
  are 
  situated 
  along 
  the 
  English 
  Channel. 
  

   (2) 
  The 
  accounts 
  obviously 
  refer 
  to 
  several 
  different 
  waves, 
  but, 
  so 
  

   far 
  as 
  one 
  wave 
  in 
  particular 
  can 
  be 
  traced, 
  it 
  advanced 
  from 
  east 
  

   to 
  west. 
  (3) 
  Similar 
  waves 
  were 
  observed 
  on 
  the 
  two 
  days 
  pre- 
  

   ceding 
  that 
  of 
  the 
  earthquake. 
  

  

  The 
  shock 
  appears 
  to 
  have 
  had 
  some 
  slight 
  effect 
  on 
  underground 
  

   water. 
  At 
  Green 
  Croft 
  (near 
  Xarberth), 
  a 
  well, 
  shortly 
  before 
  the 
  

   earthquake, 
  contained 
  some 
  water, 
  and 
  when 
  visited 
  soon 
  afterwards 
  

   was 
  found 
  to 
  be 
  empty. 
  At 
  Marloes, 
  according 
  to 
  an 
  account 
  

   written 
  about 
  eight 
  weeks 
  after 
  the 
  shock, 
  the 
  springs 
  in 
  the 
  upper 
  

   part 
  of 
  the 
  village 
  had 
  been 
  dry 
  ever 
  since, 
  while 
  the 
  lower 
  ones 
  

   were 
  overflowing. 
  

  

  Only 
  two 
  accurate 
  determinations 
  of 
  the 
  time 
  of 
  occurrence 
  appear 
  

   to 
  have 
  been 
  made 
  — 
  namely, 
  Oh. 
  24m. 
  at 
  Haverfordwest, 
  and 
  Oh. 
  

   26m. 
  at 
  Exeter. 
  Both 
  of 
  these 
  may 
  be 
  relied 
  on, 
  but, 
  being 
  given 
  

   only 
  to 
  the 
  nearest 
  minute, 
  they 
  are 
  of 
  little 
  value 
  except 
  to 
  show 
  

   that 
  the 
  surface-velocity 
  of 
  the 
  earth-wave 
  cannot 
  have 
  been 
  less 
  than 
  

   2050 
  feet 
  per 
  second. 
  No 
  traces 
  of 
  the 
  earthquake 
  are 
  to 
  be 
  discerned 
  

   on 
  the 
  magnetograms 
  of 
  Kew 
  and 
  Greenwich, 
  or 
  on 
  the 
  records 
  of 
  

   the 
  horizontal 
  pendulums 
  at 
  Strassburg 
  and 
  Nicolaiew. 
  

  

  1 
  I 
  am 
  indebted 
  to 
  the 
  Eev. 
  W. 
  M. 
  Moi 
  ris 
  for 
  this 
  account. 
  

  

  