﻿462 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  nary 
  flood-flows 
  are 
  at 
  the 
  rate 
  of 
  about 
  30 
  to 
  35 
  cubic 
  feet 
  per 
  

   second 
  per 
  square 
  mile. 
  

  

  Floods 
  in 
  Black 
  river. 
  Heavy 
  floods 
  have 
  occurred 
  in 
  Black 
  

   river 
  in 
  1807, 
  1833, 
  1850, 
  1857, 
  1862, 
  1866, 
  1869 
  and 
  1896. 
  The 
  

   flood 
  of 
  April 
  20-24, 
  1869, 
  was 
  specially 
  heavy, 
  there 
  being 
  a 
  

   heavy 
  snowfall 
  over 
  nearly 
  the 
  entire 
  catchment 
  area, 
  which 
  

   melted 
  rapidly 
  that 
  year. 
  In 
  addition 
  to 
  the 
  ground 
  being 
  heavily 
  

   covered 
  with 
  snow, 
  about 
  2.2 
  inches 
  of 
  rain 
  fell 
  in 
  some 
  parts 
  of 
  

   Black 
  river 
  catchment 
  basin 
  from 
  April 
  17-23, 
  though 
  this 
  quan- 
  

   tity 
  of 
  rain, 
  which 
  was 
  only 
  over 
  a 
  portion 
  of 
  the 
  catchment 
  area, 
  

   hardly 
  explains 
  the 
  severity 
  of 
  the 
  flood. 
  The 
  greater 
  portion 
  of 
  

   the 
  water 
  evidently 
  came 
  from 
  rapid 
  melting 
  of 
  snow. 
  

  

  Flood 
  in 
  Black 
  river 
  in 
  April, 
  1869. 
  On 
  April 
  21, 
  1869, 
  the 
  

   banks 
  of 
  North 
  lake 
  reservoir, 
  a 
  structure 
  maintained 
  by 
  the 
  State 
  

   for 
  the 
  purpose 
  of 
  storing 
  water 
  for 
  the 
  Black 
  river 
  and 
  Erie 
  

   canals, 
  gave 
  way, 
  precipitating 
  into 
  the 
  heavily 
  swollen 
  stream 
  

   about 
  350,000,000 
  cubic 
  feet 
  of 
  water. 
  This 
  accident 
  was 
  made 
  

   the 
  basis 
  of 
  large 
  claims 
  for 
  damages 
  against 
  the 
  State, 
  which 
  

   were 
  tried 
  before 
  the 
  Canal 
  Appraisers 
  in 
  the 
  summer 
  and 
  fall 
  of 
  

   1869. 
  The 
  testimony 
  in 
  this 
  case, 
  which 
  included 
  two 
  large 
  octavo 
  

   volumes 
  of 
  over 
  twelve 
  hundred 
  pages, 
  is 
  the 
  source 
  of 
  the 
  follow- 
  

   ing 
  information 
  as 
  to 
  flood-floAvs 
  of 
  Black 
  river 
  and 
  its 
  tributaries 
  

   in 
  the 
  spring 
  of 
  1869 
  : 
  

  

  The 
  Black 
  river 
  flood 
  of 
  April, 
  1869, 
  was 
  studied 
  by 
  David 
  M. 
  

   Green, 
  Samuel 
  McElroy, 
  William 
  J. 
  McAlpine, 
  L. 
  L. 
  Nichols 
  and 
  

   other 
  hydraulic 
  engineers 
  of 
  that 
  day. 
  The 
  testimony 
  may, 
  there- 
  

   fore, 
  be 
  referred 
  to 
  as 
  furnishing 
  unusually 
  good 
  flood 
  data. 
  

  

  Mr 
  Nichols 
  stated 
  that 
  he 
  not 
  only 
  measured 
  the 
  lengths 
  of 
  

   the 
  crests 
  of 
  the 
  dams 
  on 
  the 
  several 
  streams 
  for 
  which 
  flood- 
  

   flows 
  were 
  given, 
  but 
  that 
  he 
  also 
  instrumental 
  ly 
  determined 
  

   the 
  hight 
  of 
  flood 
  marks 
  above 
  the 
  crests. 
  This 
  work 
  was 
  done 
  

   within 
  a 
  few 
  months 
  after 
  the 
  flood 
  while 
  the 
  matter 
  was 
  fresh 
  

   in 
  the 
  minds 
  of 
  everybody. 
  He 
  further 
  stated 
  that 
  the 
  tabulated 
  

   flood-flows 
  were 
  obtained 
  by 
  computing 
  with 
  Francis's 
  formula 
  

   for 
  discharge 
  over 
  sharp-crested 
  weirs 
  with 
  clear 
  overfall. 
  The 
  

   dams, 
  however, 
  on 
  which 
  the 
  flood-flows 
  were 
  measured 
  were 
  of 
  

   such 
  a 
  form 
  as 
  to 
  indicate 
  the 
  use 
  of 
  Cornell 
  experiments 
  No®. 
  

  

  