﻿HYDROLOGY 
  OF 
  NEW 
  YORK 
  319 
  

  

  was 
  187.255 
  cubic 
  feet 
  per 
  second. 
  Table 
  No. 
  45, 
  giving 
  these 
  

   discharges, 
  has 
  been 
  constructed 
  by 
  substituting 
  the 
  mean 
  

   monthly 
  elevations 
  of 
  Lake 
  Erie 
  from 
  the 
  preceding 
  table 
  in 
  the 
  

   formula 
  for 
  discharge 
  of 
  Niagara 
  river. 
  It 
  extends 
  from 
  3.865- 
  

   1898, 
  inclusive. 
  

  

  It 
  will 
  be 
  noticed 
  that 
  on 
  a 
  preceding 
  page 
  the 
  writer 
  states 
  that 
  

   the 
  mean 
  discharge 
  for 
  a 
  year 
  may 
  be 
  as 
  low 
  as 
  177,700' 
  cubic 
  feet 
  

   per 
  second, 
  or 
  not 
  exceeding 
  about 
  6 
  inches 
  in 
  depth 
  over 
  the 
  entire 
  

   catchment 
  area. 
  For 
  the 
  year 
  1895 
  the 
  mean 
  discharge 
  for 
  the 
  

   entire 
  year 
  was 
  only 
  10,000 
  cubic 
  feet 
  per 
  second 
  in 
  excess 
  of 
  

   this 
  figure, 
  but 
  it 
  is 
  certain 
  that 
  1895, 
  while 
  a 
  low 
  year, 
  was 
  not 
  

   absolutely 
  the 
  minimum 
  year. 
  In 
  view 
  of 
  the 
  foregoing, 
  it 
  is 
  

   believed 
  that 
  when 
  properly 
  used, 
  intelligent 
  analysis 
  of 
  rainfall, 
  

   runoff 
  and 
  evaporation 
  may 
  be 
  sufficient 
  to 
  settle 
  such 
  a 
  question. 
  

  

  The 
  literature 
  of 
  the 
  discharge 
  of 
  Niagara 
  river 
  and 
  of 
  the 
  

   probable 
  effect 
  on 
  the 
  lake 
  levels 
  of 
  abstracting 
  10,000 
  cubic 
  feet 
  

   per 
  second 
  at 
  Chicago 
  has 
  grown 
  so 
  extensive 
  as 
  to 
  preclude 
  fur- 
  

   ther 
  discussion 
  here. 
  Those 
  wishing 
  to 
  pursue 
  the 
  subject 
  may 
  

   consult 
  the 
  references 
  given 
  in 
  the 
  footnote. 
  

  

  The 
  following 
  is 
  a 
  summary 
  of 
  the 
  matter 
  : 
  

  

  1) 
  The 
  studies 
  of 
  the 
  Lake 
  Survey 
  indicate 
  a 
  mean 
  discharge 
  

   of 
  Niagara 
  river 
  of 
  about 
  265,000 
  cubic 
  feet 
  per 
  second, 
  with 
  a 
  

   range 
  above 
  and 
  below 
  the 
  mean 
  of 
  from 
  20 
  per 
  cent 
  to 
  30 
  per 
  

   tent. 
  

  

  2) 
  The 
  measurements 
  made 
  from 
  December 
  to 
  May, 
  1891-92, 
  

   indicate 
  a 
  minimum 
  discharge 
  as 
  low, 
  or 
  even 
  lower, 
  than 
  141,000 
  

   cubic 
  feet 
  per 
  second. 
  

  

  3) 
  The 
  measurements 
  of 
  the 
  Board 
  of 
  Engineers 
  on 
  Deep 
  

   Waterways, 
  made 
  in 
  1898-99, 
  indicate 
  a 
  mean 
  discharge 
  from 
  

   1865-1898, 
  inclusive, 
  of 
  220,000 
  cubic 
  feet 
  per 
  second, 
  while 
  for 
  

   the 
  year 
  1895 
  the 
  mean 
  for 
  the 
  whole 
  year 
  is 
  only 
  187,000 
  cubic 
  

   feet 
  per 
  second. 
  

  

  4) 
  Based 
  on 
  theoretical 
  considerations 
  purely, 
  the 
  writer 
  in 
  

   1897 
  estimated 
  the 
  minimum 
  mean 
  discharge 
  for 
  a 
  series 
  of 
  dry 
  

   years 
  at 
  178,000 
  cubic 
  feet 
  per 
  second, 
  or 
  at 
  the 
  rate 
  of 
  6 
  inches 
  

   in 
  depth 
  over 
  the 
  entire 
  catchment 
  area. 
  The 
  writer 
  considers 
  

   that 
  this 
  latter 
  figure 
  is 
  more 
  nearly 
  right 
  than 
  any 
  estimate 
  

  

  