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  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  A 
  record 
  of 
  floods 
  has 
  also 
  been 
  kept 
  on 
  a 
  number 
  of 
  other 
  

   important 
  French 
  rivers, 
  as 
  the 
  Garonne, 
  of 
  which 
  special 
  studies 
  

   were 
  made 
  over 
  forty 
  years 
  ago, 
  the 
  Loire 
  and 
  the 
  Khone, 
  all 
  of 
  

   which 
  are 
  the 
  subject- 
  of 
  special 
  extended 
  memoirs. 
  

  

  A 
  number 
  of 
  rivers 
  of 
  Germany 
  and 
  Austria 
  have 
  been 
  studied 
  

   carefully 
  for 
  from 
  50 
  to 
  100 
  years, 
  but 
  in 
  the 
  United 
  States 
  sub- 
  

   stantially 
  nothing 
  had 
  been 
  done 
  until 
  about 
  twenty 
  years 
  ago, 
  

   from 
  whence 
  it 
  results 
  that 
  river 
  conservancy 
  is 
  a 
  new 
  subject 
  

   here, 
  many 
  persons 
  supposing 
  that 
  nothing 
  has 
  ever 
  been 
  done 
  

   anywhere. 
  

  

  Definition 
  of 
  river 
  regulation 
  or 
  conservancy. 
  The 
  term 
  river 
  

   regulation 
  or 
  conservancy 
  may 
  be 
  considered 
  as 
  comprising 
  the 
  

   following 
  objects 
  : 
  

  

  1) 
  The 
  preservation 
  and 
  improvement 
  of 
  a 
  stream 
  for 
  domes- 
  

   tic, 
  sanitary 
  and 
  industrial 
  purposes. 
  

  

  2) 
  In 
  the 
  case 
  of 
  navigable 
  streams, 
  their 
  maintenance 
  and 
  

   regulation 
  for 
  navigation. 
  

  

  3) 
  The 
  culture 
  and 
  preservation 
  of 
  fish. 
  

  

  4) 
  The 
  effectual 
  drainage 
  of 
  the 
  district 
  through 
  which 
  a 
  

   stream 
  runs. 
  

  

  5) 
  The 
  abatement 
  of 
  injury 
  to 
  lands 
  by 
  floods. 
  

  

  The 
  cause 
  of 
  floods 
  is, 
  broadly, 
  excessive 
  and 
  irregular 
  rain- 
  

   fall, 
  although 
  very 
  heavy 
  rainfalls 
  may 
  occur 
  without 
  causing 
  

   a 
  flood. 
  General 
  statements 
  of 
  why 
  this 
  is 
  so 
  have 
  been 
  made 
  

   in 
  the 
  preceding 
  paragraph 
  regarding 
  the 
  river 
  Seine. 
  Indeed, 
  

   an 
  investigation 
  into 
  rainfall 
  shows 
  that 
  the 
  intensity 
  of 
  floods 
  

   is 
  due 
  only 
  very 
  remotely 
  to 
  the 
  amount 
  of 
  rainfall. 
  On 
  the 
  

   contrary, 
  floods 
  are 
  very 
  closely 
  related 
  to 
  hight 
  of 
  ground 
  

   water. 
  On 
  Genesee 
  river, 
  in 
  August, 
  1893, 
  when 
  as 
  the 
  result 
  of 
  

   a 
  serious 
  summer 
  drought 
  ground 
  water 
  was 
  very 
  low, 
  a 
  rainfall 
  

   of 
  several 
  inches 
  only 
  produced 
  a 
  slight 
  flood 
  of 
  about 
  4000 
  cubic 
  

   feet 
  per 
  second, 
  whereas 
  in 
  July, 
  1902, 
  preceded 
  by 
  rain 
  enough 
  

   to 
  fill 
  the 
  ground 
  with 
  water, 
  about 
  the 
  same 
  amount 
  of 
  sud- 
  

   den 
  rainfall 
  produced 
  a 
  devastating 
  flood 
  of 
  from 
  20,000 
  to 
  

   30,000 
  cubic 
  feet 
  per 
  second. 
  1 
  Many 
  other 
  examples 
  could 
  be 
  

  

  i 
  Floods 
  on 
  Genesee 
  river 
  vary 
  greatly 
  in 
  intensity. 
  A 
  flood 
  of 
  from 
  

   30,000 
  to 
  40,000 
  cubic 
  feet 
  per 
  second 
  at 
  Mount 
  Morris 
  is 
  not 
  likely 
  to 
  pro- 
  

   duce, 
  owing 
  to 
  temporary 
  storage 
  on 
  the 
  flats, 
  a 
  flood 
  of 
  more 
  than 
  20,000 
  

   cubic 
  feet 
  per 
  second 
  at 
  Rochester. 
  The 
  preceding 
  statement 
  considers 
  the 
  

   flood 
  as 
  measured 
  at 
  Mount 
  Morris. 
  

  

  