﻿168 
  DR. 
  C. 
  DAVISON 
  ON 
  THE 
  PEMBROKE 
  EARTHQUAKES 
  [May 
  1897, 
  

  

  as 
  a 
  very 
  slight 
  quiver. 
  There 
  are 
  no 
  records 
  of 
  any 
  sound 
  being 
  

   heard 
  to 
  accompany 
  it, 
  and 
  in 
  this 
  respect 
  it 
  is 
  almost 
  unique 
  in 
  

   the 
  annals 
  of 
  recent 
  British 
  earthquakes. 
  The 
  chief 
  interest 
  of 
  

   this 
  shock 
  and 
  of 
  that 
  of 
  Aug. 
  22nd 
  (Jc) 
  lies 
  in 
  the 
  fact 
  that 
  the 
  longer 
  

   axes 
  of 
  their 
  disturbed 
  areas 
  are 
  at 
  right 
  angles 
  to 
  those 
  of 
  the 
  

   preceding 
  earthquakes. 
  

  

  i. 
  August 
  19 
  : 
  9.30 
  a.m. 
  

  

  I 
  have 
  received 
  only 
  one 
  record 
  of 
  this 
  earth-sound. 
  At 
  

   St. 
  David's, 
  Dr. 
  "W. 
  P. 
  Propert 
  heard 
  a 
  noise 
  like 
  thunder, 
  but 
  

   more 
  crashing 
  and 
  grating, 
  without 
  any 
  accompanying 
  vibration. 
  

   As 
  most 
  of 
  the 
  previous 
  shocks 
  were 
  felt 
  by 
  this 
  observer, 
  it 
  

   appears 
  to 
  me 
  that, 
  though 
  a 
  solitary 
  record, 
  much 
  reliance 
  may 
  

   be 
  placed 
  upon 
  it. 
  

  

  k. 
  August 
  22nd 
  : 
  about 
  11.55 
  a.m. 
  

  

  Intensity, 
  4. 
  — 
  Number 
  of 
  records, 
  21 
  ; 
  from 
  13 
  different 
  places. 
  

  

  The 
  boundary 
  of 
  the 
  disturbed 
  area 
  is 
  a 
  narrow 
  oval, 
  19 
  miles 
  

   long, 
  7^ 
  miles 
  broad, 
  and 
  containing 
  about 
  112 
  square 
  miles. 
  Its 
  

   longer 
  axis 
  runs 
  east 
  and 
  west, 
  and 
  lies 
  about 
  1| 
  mile 
  north 
  of 
  

   that 
  of 
  the 
  last 
  earthquake 
  (h) 
  on 
  Aug. 
  18. 
  The 
  centre 
  of 
  the 
  curve 
  

   is 
  at 
  a 
  point 
  1| 
  mile 
  west 
  of 
  Honeyborough. 
  (See 
  map, 
  p. 
  158.) 
  

  

  The 
  shock 
  consisted 
  of 
  a 
  slight 
  tremor. 
  It 
  was 
  strongest 
  at 
  

   Pembroke 
  Dock, 
  where 
  three 
  slight 
  shocks 
  of 
  equal 
  intensity 
  were 
  

   felt 
  at 
  intervals 
  of 
  about 
  3 
  or 
  4 
  seconds, 
  The 
  sound, 
  a 
  slight 
  

   rumbling 
  like 
  the 
  firing 
  of 
  a 
  distant 
  gun, 
  was 
  observed 
  at 
  only 
  

   6 
  places. 
  

  

  1. 
  August 
  23rd 
  : 
  4.30 
  a.m. 
  

  

  A 
  slight 
  vibration, 
  felt 
  by 
  several 
  observers 
  in 
  one 
  house 
  at 
  

   Pembroke 
  Dock. 
  

  

  II. 
  — 
  Earthquakes 
  oe 
  November 
  2nd-3rd, 
  1893. 
  

  

  Only 
  four 
  undoubted 
  earthquakes 
  belong 
  to 
  this 
  series. 
  The 
  

   principal 
  earthquake 
  is 
  indicated 
  by 
  a 
  capital 
  letter. 
  

  

  A. 
  Nov. 
  2nd 
  : 
  5.45 
  p.m. 
  

  

  b. 
  „ 
  6.1 
  p.m. 
  

  

  c. 
  „ 
  about 
  6.15 
  or 
  6.S0 
  p.m. 
  

  

  d. 
  Nov. 
  3rd: 
  „ 
  1 
  a.m. 
  

  

  At 
  Kidwelly 
  (Caermarthen 
  shire), 
  a 
  rumbling 
  noise 
  was 
  heard 
  25 
  

   seconds 
  before 
  the 
  principal 
  shock.. 
  Also, 
  at 
  Hafren 
  Hall, 
  in 
  the 
  

   same 
  county, 
  noises 
  like 
  distant 
  thunder 
  were 
  heard 
  at 
  intervals 
  

   during 
  the 
  afternoon, 
  no 
  tremulous 
  motion 
  being 
  felt. 
  It 
  is 
  

   doubtful 
  whether 
  these 
  were 
  of 
  seismic 
  origin. 
  

  

  