﻿374 
  OLDHAM: 
  GREAT 
  EARTHQUAKE 
  OF 
  189/. 
  

  

  continued 
  for 
  about 
  half 
  a 
  minute, 
  gradually 
  decreasing, 
  or 
  appearing 
  at 
  a 
  greatei* 
  

   distance. 
  They 
  imagined, 
  that 
  the 
  whole 
  space 
  of 
  time, 
  from 
  the 
  first 
  shock 
  to 
  

   the 
  last, 
  was 
  about 
  twenty 
  minutes 
  ; 
  and 
  they 
  tarried 
  about 
  ten 
  minutes 
  in 
  the 
  

   mine 
  after 
  the 
  last 
  shock 
  J 
  when 
  they 
  thought 
  it 
  advisable 
  to 
  examine 
  the 
  passage 
  

   and 
  to 
  get 
  out 
  of 
  the 
  mine, 
  if 
  possible. 
  As 
  they 
  went 
  along 
  the 
  drifts, 
  they 
  

   observed 
  that 
  several 
  pieces 
  of 
  minerals 
  were 
  dropped 
  from 
  the 
  sides 
  and 
  roof, 
  but 
  

   all 
  the 
  shafts 
  remained 
  entire 
  without 
  the 
  least 
  discomposure. 
  

  

  The 
  space 
  of 
  ground 
  at 
  the 
  aforesaid 
  mines 
  wherein 
  it 
  was 
  felt, 
  was 
  960 
  yards 
  

   which 
  was 
  all 
  that 
  was 
  at 
  that 
  time 
  in 
  workmanship. 
  1 
  

  

  From 
  this 
  account 
  it 
  is 
  evident 
  that 
  we 
  are 
  dealing, 
  not 
  with 
  the 
  Lisbon 
  earth- 
  

   quake, 
  but 
  with 
  an 
  independent 
  one 
  of 
  local 
  origin. 
  Too 
  much 
  importance 
  must 
  

   not 
  be 
  attached 
  to 
  the 
  reported 
  time, 
  which 
  is 
  an 
  hour 
  later 
  than 
  that 
  of 
  the 
  Lisbon 
  

   shock, 
  as 
  it 
  is 
  evidently 
  only 
  approximate, 
  but 
  the 
  shock 
  described 
  is 
  a 
  fairly 
  severe 
  

   one, 
  much 
  severer 
  than 
  indicated 
  by 
  any 
  of 
  the 
  accounts 
  of 
  the 
  shock 
  in 
  or 
  out 
  of 
  

   England, 
  till 
  we 
  get 
  to 
  the 
  south-western 
  part 
  of 
  France. 
  

  

  Besides 
  the 
  severity 
  of 
  the 
  shock 
  there 
  is 
  the 
  fact 
  that 
  it 
  was'felt 
  underground 
  

   almost 
  as 
  severely 
  as 
  at 
  the 
  surface. 
  With 
  regard 
  to 
  earthquakes 
  generally 
  

   it 
  seems 
  well 
  established 
  that, 
  in 
  the 
  area 
  of 
  propagation, 
  the 
  motion 
  that 
  can 
  be 
  

   felt 
  is 
  confined 
  to 
  the 
  surface 
  and, 
  at 
  a 
  very 
  small 
  depth 
  below 
  ground, 
  it 
  ceases 
  to 
  

   be 
  felt. 
  Within 
  the 
  area 
  of 
  the 
  epicentre, 
  however, 
  or 
  even 
  within 
  that 
  of 
  the 
  earth- 
  

   quake 
  core, 
  there 
  is 
  no 
  reason 
  why 
  this 
  should 
  be 
  so, 
  and 
  the 
  account 
  of 
  what 
  was 
  

   felt 
  in 
  the 
  Eyam-edge 
  mine 
  points 
  to 
  its 
  being 
  on 
  the 
  direct 
  path 
  upwards 
  from 
  

   the 
  focus 
  to 
  the 
  surface 
  ; 
  a 
  supposition 
  which 
  is 
  borne 
  out 
  by 
  the 
  large 
  vertical 
  

   component 
  of 
  the 
  motion 
  indicated 
  in 
  the 
  overseer's 
  account. 
  

  

  The 
  Derbyshire 
  earthquake 
  may 
  consequently 
  be 
  excluded 
  from 
  the 
  accounts 
  o! 
  

   the 
  Lisbon 
  earthquake 
  j 
  at 
  the 
  most 
  it 
  can 
  only 
  be 
  connected 
  with 
  the 
  greater 
  

   shock 
  as 
  a 
  sympathetic 
  earthquake, 
  and 
  even 
  that 
  is 
  doubtful. 
  

  

  With 
  the 
  exception 
  of 
  the 
  Derbyshire 
  earthquake 
  all 
  the 
  other 
  accounts 
  col- 
  

   lected 
  by 
  the 
  Royal 
  Society, 
  and 
  published 
  in 
  the 
  49th 
  volume 
  of 
  its 
  Philosophical 
  

   Transactions, 
  relate 
  merely 
  to 
  the 
  effects 
  of 
  the 
  sea-waves 
  along 
  the 
  coasts, 
  or 
  

   oscillations 
  of 
  ponds, 
  canals, 
  and 
  even 
  lakes, 
  similar 
  to 
  those 
  described 
  in 
  Burma, 
  2 
  

   in 
  the 
  case 
  of 
  the 
  1897 
  shock. 
  One 
  account 
  alone 
  mentions 
  the 
  earthquake 
  as 
  

   having 
  been 
  felt 
  near 
  Reading; 
  Mr. 
  Paunceforth's 
  gardener 
  stated 
  that 
  he 
  felt 
  

   a 
  most 
  violent 
  trembling 
  of 
  the 
  earth 
  for 
  fifty 
  seconds. 
  All 
  the 
  other 
  accounts 
  

   either 
  definitely 
  state 
  that 
  no 
  shock 
  could 
  be 
  felt, 
  or, 
  in 
  a 
  few 
  instances, 
  say 
  

   nothing 
  as 
  to 
  this, 
  and 
  it 
  is 
  probable 
  that 
  the 
  violent 
  trembling 
  felt 
  by 
  Mr 
  # 
  

   Paunceforth's 
  gardener, 
  who 
  was 
  watching 
  the 
  washing 
  back 
  and 
  forwards 
  of 
  

   water 
  in 
  a 
  pond, 
  was 
  the 
  result 
  of 
  imagination. 
  

  

  In 
  the 
  accounts 
  of 
  the 
  shock 
  as 
  experienced 
  in 
  Holland 
  and 
  Denmark, 
  I 
  can 
  

   find 
  nothing 
  to 
  support 
  the 
  idea 
  that 
  it 
  was 
  felt 
  there, 
  only 
  oscillations 
  of 
  water 
  in 
  

   ponds 
  and 
  canals 
  are 
  recorded 
  ; 
  while 
  the 
  time 
  at 
  which 
  the 
  shock 
  is 
  said 
  to 
  have 
  

   been 
  felt 
  in 
  southern 
  Norway, 
  4 
  a.m., 
  shows 
  that 
  the 
  shock, 
  which 
  was 
  certainly 
  

  

  1 
  Phil. 
  Trans. 
  XLIX, 
  pp., 
  399 
  ff. 
  

   2 
  See 
  chapter 
  II, 
  page 
  39. 
  

  

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