﻿24$ 
  

  

  Oldham: 
  great 
  earthquake 
  of 
  1897. 
  

  

  

  Interval 
  in 
  

   minutes. 
  

  

  APPARENT 
  RATE 
  OF 
  TRAVEL 
  ALONG 
  

  

  

  Surface. 
  

  

  Direct 
  line. 
  

  

  

  Miles 
  per 
  

   minute. 
  

  

  Kilometres 
  

   per 
  second. 
  

  

  Miles 
  per 
  Kilometres 
  

   minute. 
  per 
  second. 
  

  

  Ischia 
  . 
  . 
  . 
  . 
  

  

  2S'0 
  

  

  209 
  

  

  5'52 
  

  

  198 
  

  

  5' 
  24 
  

  

  Catania 
  . 
  

  

  2i'o 
  

  

  210 
  

  

  5*56 
  

  

  199 
  

  

  5*27 
  

  

  Rome, 
  Rocca 
  di 
  Papa 
  

  

  2075 
  

  

  213 
  

  

  5*64 
  

  

  202 
  

  

  5'35 
  

  

  ,, 
  Ufficio 
  centrale 
  . 
  

  

  20*25 
  

  

  214 
  

  

  578 
  

  

  207 
  

  

  S'& 
  

  

  Padua 
  . 
  

  

  2075 
  

  

  215 
  

  

  5'68 
  

  

  203 
  

  

  5'2>S 
  

  

  Siena 
  . 
  . 
  . 
  . 
  

  

  2I*0 
  

  

  215 
  

  

  5"6"9 
  

  

  203 
  

  

  5-38 
  

  

  Arithmetical 
  mean 
  . 
  

  

  207 
  

  

  213 
  

  

  5'64 
  

  

  202 
  

  

  5"35 
  

  

  Edinburgh 
  

  

  23*0 
  

  

  213 
  

  

  5*63 
  

  

  200 
  

  

  5-29 
  

  

  Here 
  we 
  have 
  a 
  rate 
  of 
  propagation 
  of 
  about 
  200 
  miles 
  a 
  minute, 
  

   or 
  5*3 
  kilometres 
  a 
  second, 
  lower 
  than 
  that 
  of 
  the 
  preliminary 
  

   vibration, 
  but 
  still 
  much 
  greater 
  than 
  that 
  of 
  the 
  sensible 
  earthquake 
  

   in 
  the 
  region 
  where 
  it 
  could 
  be 
  recognised 
  without 
  instrumental 
  aid. 
  

  

  There 
  remains 
  only 
  the 
  group 
  of 
  large 
  undulations, 
  lasting 
  for 
  

   about 
  10 
  minutes. 
  It 
  is 
  only 
  in 
  the 
  Italian 
  records 
  that 
  these 
  can 
  be 
  

   recognised, 
  as 
  the 
  oscillations 
  at 
  this 
  period 
  were 
  too 
  extensive 
  to 
  

   allow 
  an 
  impression 
  being 
  made 
  on 
  the 
  sensitive 
  paper 
  where 
  photo- 
  

   graphic 
  registration 
  was 
  employed. 
  

  

  For 
  the 
  commencement 
  of 
  these 
  oscillations, 
  we 
  have 
  the 
  follow- 
  

   ing 
  result 
  : 
  — 
  

  

  

  Interval 
  

   in 
  

  

  APPARENT 
  RATE 
  OF 
  TRAVEL 
  ALONG 
  

  

  

  Surface. 
  

  

  Direct 
  line. 
  

  

  

  

  

  

  

  

  minutes. 
  

  

  Miles 
  per 
  

  

  Kilometres 
  

  

  Miles 
  per 
  

  

  Kilometres 
  

  

  

  

  minute. 
  

  

  per 
  second. 
  

  

  minute. 
  

  

  per 
  second. 
  

  

  Ischia 
  .... 
  

  

  37*5 
  

  

  117 
  

  

  3*09 
  

  

  in 
  

  

  2-94 
  

  

  Catania 
  .... 
  

  

  40 
  

  

  no 
  

  

  2*92 
  

  

  105 
  

  

  277 
  

  

  Rome, 
  Rocca 
  di 
  Papa 
  

  

  367S 
  

  

  120 
  

  

  3*19 
  

  

  114 
  

  

  . 
  3'o2 
  

  

  ,, 
  Ufficio 
  centrale 
  . 
  

  

  38*0 
  

  

  116 
  

  

  3 
  '08 
  

  

  no 
  

  

  2*92 
  

  

  ( 
  248 
  ) 
  

  

  