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  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  There 
  are 
  rounded 
  aggregates 
  which 
  may 
  represent 
  an 
  earlier 
  gen- 
  

   eration, 
  perhaps 
  derived 
  from 
  a 
  silicate 
  mineral 
  of 
  the 
  pyroxene 
  

   or 
  hornblende 
  family. 
  The 
  talc 
  nodules 
  are 
  frequently 
  bordered 
  

   by 
  veins 
  of 
  massive 
  serpentine 
  that 
  appear 
  to 
  have 
  resulted 
  as 
  a 
  

   reaction 
  from 
  contact 
  of 
  the 
  talc 
  with 
  iron-bearing 
  solutions. 
  The 
  

   limestones 
  at 
  this 
  place 
  have 
  undergone 
  considerable 
  disturbances 
  

   from 
  regional 
  compression 
  since 
  the 
  deposition 
  of 
  the 
  ores, 
  mani- 
  

   fested 
  by 
  the 
  brecciated 
  and 
  faulted 
  condition 
  of 
  the 
  deposits 
  in 
  

   certain 
  places 
  and 
  the 
  flowage 
  of 
  the 
  limestones 
  into 
  the 
  fractures 
  

   so 
  as 
  to 
  cement 
  the 
  broken 
  and 
  disjointed 
  parts. 
  The 
  whole 
  min- 
  

   eral 
  association 
  seems 
  referable 
  to 
  the 
  work 
  of 
  underground 
  waters 
  

   which 
  in 
  a 
  period 
  of 
  long-continued 
  circulation 
  have 
  introduced 
  and 
  

   deposited 
  various 
  ingredients. 
  There 
  is 
  insufficient 
  evidence, 
  as 
  

   yet, 
  to 
  connect 
  the 
  mineralization 
  with 
  igneous 
  agencies, 
  and 
  if 
  these 
  

   have 
  been 
  a 
  factor, 
  they 
  were 
  no 
  doubt 
  connected 
  with 
  the 
  granite 
  

   invasion, 
  the 
  only 
  intrusive 
  that 
  has 
  any 
  prominence 
  in 
  the 
  district. 
  

  

  SEISMOLOGIC 
  STATION 
  

  

  The 
  year's 
  records 
  for 
  the 
  local 
  seismologic 
  station 
  are 
  given 
  in 
  

   the 
  accompanying 
  table 
  in 
  conformity 
  with 
  the 
  plan 
  previously 
  used 
  

   in 
  leporting 
  the 
  data. 
  The 
  list, 
  it 
  may 
  be 
  noted, 
  includes 
  only 
  such 
  

   disturbances 
  as 
  set 
  up 
  prolonged 
  and 
  well-marked 
  vibrational 
  move- 
  

   ments, 
  usually 
  differentiated 
  into 
  phases 
  — 
  such 
  as 
  are 
  referable 
  

   without 
  much 
  doubt 
  to 
  true 
  tectonic 
  shocks 
  transmitted 
  to 
  the 
  sta- 
  

   tion 
  from 
  more 
  or 
  less 
  remote 
  origins. 
  Of 
  almost 
  daily 
  occurrence 
  

   are 
  brief 
  or 
  indistinct 
  motions 
  arising 
  from 
  various 
  causes 
  not 
  

   wholly 
  explained, 
  but 
  these 
  have 
  not 
  been 
  taken 
  into 
  account 
  in 
  the 
  

   table. 
  

  

  The 
  number 
  of 
  individual 
  tracings 
  of 
  earthquakes 
  obtained 
  within 
  

   the 
  year 
  ending 
  September 
  30, 
  1912 
  was 
  twelve, 
  as 
  compared 
  with 
  

   nine 
  in 
  the 
  preceding 
  period, 
  and 
  nineteen 
  in 
  the 
  year 
  1909-10. 
  

   This 
  record 
  seems 
  to 
  indicate 
  a 
  general 
  falling 
  off 
  of 
  late 
  in 
  seismic 
  

   frequency, 
  at 
  least 
  with 
  respect 
  to 
  the 
  heavier 
  shocks 
  which 
  are 
  

   recorded 
  mainly 
  at 
  the 
  Albany 
  station. 
  There 
  have 
  been 
  at 
  the 
  

   same 
  time 
  few 
  destructive 
  disturbances 
  ; 
  within 
  the 
  past 
  year, 
  none 
  

   has 
  transmitted 
  vibrations 
  that 
  exceeded 
  the 
  capacity 
  of 
  the 
  instru- 
  

   ment 
  for 
  registration. 
  

  

  Since 
  the 
  station 
  was 
  established 
  in 
  March 
  1906, 
  it 
  has 
  supplied 
  

   data 
  in 
  regard 
  to 
  ninety-eight 
  individual 
  shocks. 
  In 
  view 
  of 
  the 
  

   fact 
  that 
  the 
  installation 
  represents 
  an 
  early 
  type, 
  comparatively, 
  

   the 
  results 
  may 
  be 
  considered 
  quite 
  satisfactory. 
  They 
  sufficiently 
  

   demonstrate 
  that 
  the 
  somewhat 
  peculiar 
  conditions 
  existing 
  in 
  this 
  

  

  