﻿82 
  OLDHAM 
  : 
  GREAT 
  EARTHQUAKE 
  OF 
  1897. 
  

  

  amplitude, 
  and 
  period 
  of 
  an 
  elastic 
  wave, 
  are 
  so 
  related 
  to 
  each 
  other 
  

   that, 
  given 
  any 
  two, 
  the 
  others 
  can 
  be 
  determined, 
  it 
  might 
  be 
  thought 
  

   that 
  from 
  the 
  data 
  available 
  we 
  could 
  deduce 
  both 
  amplitude 
  and 
  

   period 
  of 
  the 
  earthquake 
  wave 
  ; 
  and 
  from 
  the 
  data 
  so 
  obtained 
  to 
  

   form 
  some 
  idea 
  of 
  the 
  violence 
  which 
  accompanied 
  the 
  high 
  velocity 
  

   obtained 
  at 
  Rembrai. 
  When 
  this 
  is 
  attempted, 
  however, 
  it 
  is 
  found 
  

   that 
  the 
  results 
  are 
  absurd, 
  and 
  the 
  only 
  possible 
  conclusion 
  that 
  can 
  

   be 
  come 
  to 
  is 
  that 
  the 
  high 
  velocities 
  of 
  movement 
  required 
  to 
  ac- 
  

   count 
  for 
  the 
  way 
  in 
  which 
  stones 
  were 
  shot 
  through 
  the 
  air, 
  

   to 
  a 
  distance 
  of 
  as 
  much 
  as 
  8J 
  feet, 
  were 
  not 
  those 
  of 
  the 
  earthquake 
  

   wave, 
  but 
  due 
  to 
  bodily 
  displacements 
  of 
  the 
  ground 
  ; 
  movements 
  

   which 
  left 
  the 
  hills 
  permanently 
  higher 
  than 
  they 
  had 
  been 
  before 
  

   the 
  earthquake. 
  1 
  

  

  As 
  this 
  means 
  that 
  the 
  motion 
  of 
  the 
  ground 
  due 
  to 
  the 
  earth- 
  

   quake 
  waves 
  was 
  complicated 
  by 
  movements 
  of 
  a 
  much 
  larger 
  scale 
  

   of 
  a 
  very 
  different 
  character, 
  it 
  is 
  evident 
  that 
  we 
  cannot 
  employ 
  the 
  

   high 
  velocities 
  obtained 
  at 
  Rembrai 
  to 
  form 
  any 
  sort 
  of 
  estimate 
  of 
  

   the 
  acceleration, 
  or 
  violence, 
  of 
  the 
  earthquake 
  at 
  that 
  place. 
  We 
  

   are 
  thus 
  deprived 
  of 
  the 
  only 
  means 
  of 
  attaining 
  even 
  an 
  approximate 
  

   estimate 
  of 
  the 
  extreme 
  violence 
  attained 
  by 
  the 
  earthquake, 
  

   and 
  must 
  remain 
  content 
  with 
  such 
  vague 
  guesses 
  as 
  have 
  been 
  

   attempted. 
  

  

  The 
  only 
  direct 
  measure 
  of 
  the 
  amplitude 
  of 
  the 
  wave, 
  or 
  of 
  the 
  

   greatest 
  backward 
  and 
  forward 
  movement 
  of 
  the 
  wave 
  particle, 
  was 
  

   at 
  Cherrapunji. 
  Two 
  oblong 
  masonry 
  tombs, 
  standing 
  close 
  together 
  

   and 
  oriented 
  with 
  their 
  longer 
  axes 
  north 
  and 
  south, 
  have 
  been 
  

   partially 
  destroyed 
  on 
  the 
  inner 
  sides, 
  the 
  space 
  between 
  them 
  being 
  

   filled 
  with 
  debris. 
  On 
  the 
  outer 
  sides, 
  they 
  are 
  almost 
  intact, 
  but 
  the 
  

   tombs 
  have 
  been 
  driven 
  bodily 
  down 
  into 
  the 
  ground, 
  and 
  on 
  either 
  

   side, 
  to 
  east 
  and 
  west, 
  there 
  is 
  a 
  depression 
  with 
  a 
  vertical 
  side 
  

   parallel 
  to 
  the 
  outer 
  surface 
  of 
  the 
  tomb 
  and 
  a 
  smooth 
  flat 
  bottom 
  

  

  ' 
  See 
  Appendix 
  C. 
  

  

  ( 
  82 
  ) 
  

  

  