﻿HYDROLOGY 
  OF 
  NEW 
  YORK 
  173 
  

  

  effect, 
  such 
  as 
  the 
  diminution 
  of 
  rivers 
  and 
  the 
  drying 
  up 
  of 
  

   streams 
  and 
  springs. 
  Other 
  effects, 
  scarcely 
  less 
  certain, 
  are 
  seen 
  

   in 
  the 
  occurrence 
  of 
  destructive 
  floods, 
  and 
  of 
  unseasonable 
  and 
  

   prolonged 
  droughts, 
  with 
  other 
  vicissitudes 
  of 
  climate 
  which 
  it 
  

   is 
  alleged 
  did 
  not 
  occur 
  when 
  the 
  country 
  was 
  covered 
  with 
  forests. 
  

   These 
  appear 
  to 
  have 
  been 
  brought 
  about 
  by 
  their 
  removal, 
  and 
  

   might, 
  in 
  a 
  great 
  degree, 
  be 
  alleviated 
  by 
  the 
  restoration 
  of 
  wood- 
  

   lands 
  to 
  a 
  degree 
  consistent 
  with 
  our 
  best 
  agricultural 
  interests. 
  

  

  On 
  the 
  other 
  hand, 
  there 
  are 
  many 
  facts 
  tending 
  to 
  show 
  that 
  

   the 
  presence 
  or 
  absence 
  and 
  the 
  character 
  of 
  forests 
  are 
  the 
  effect 
  

   of 
  climate, 
  and 
  that 
  their 
  cultivation 
  generally, 
  or 
  the 
  planting 
  of 
  

   particular 
  species, 
  is 
  closely 
  dependent 
  upon 
  it. 
  These 
  conditions 
  

   of 
  climate 
  should 
  be 
  understood 
  before 
  forest 
  cultivation 
  is 
  

   attempted. 
  It 
  is 
  also 
  to 
  be 
  noticed 
  that 
  differences 
  of 
  opinion 
  

   have 
  been 
  expressed 
  among 
  men 
  of 
  science 
  as 
  to 
  the 
  extent 
  of 
  

   influence 
  that 
  forests 
  exert 
  upon 
  the 
  climate, 
  and 
  it 
  is 
  quite 
  prob- 
  

   able 
  that 
  the 
  advocates 
  of 
  extreme 
  theories 
  may 
  have 
  erred 
  on 
  

   both 
  sides. 
  But 
  where 
  principles 
  depend 
  upon 
  facts 
  that 
  may 
  be 
  

   settled 
  by 
  observation, 
  there 
  should 
  be 
  no 
  differences 
  of 
  opinion 
  ; 
  

   and 
  as 
  there 
  is 
  no 
  fact 
  in 
  this 
  subject 
  that 
  may 
  not 
  be 
  verified 
  or 
  

   disproved, 
  the 
  existence 
  of 
  such 
  differences 
  only 
  shows 
  the 
  want 
  

   of 
  accepted 
  evidence 
  derived 
  from 
  trustworthy 
  records. 
  

  

  The 
  interested 
  reader 
  is 
  referred 
  to 
  Dr 
  Hough's 
  report, 
  which 
  

   may 
  be 
  easily 
  obtained, 
  for 
  an 
  extended 
  discussion 
  on 
  this 
  point. 
  

  

  Relation 
  of 
  forests 
  to 
  stream 
  flow. 
  The 
  extent 
  of 
  forestation 
  

   has 
  probably 
  a 
  considerable 
  effect 
  on 
  the 
  runoff 
  of 
  streams. 
  With 
  

   similar 
  rainfalls, 
  two 
  streams, 
  one 
  in 
  a 
  region 
  having 
  dense 
  

   primeval 
  forests, 
  the 
  other 
  in 
  a 
  region 
  wmolly 
  or 
  partially 
  

   deforested, 
  will 
  show 
  different 
  runoff. 
  The 
  one 
  with 
  the 
  dense 
  

   forests 
  will 
  show 
  larger 
  runoff 
  than 
  the 
  stream 
  in 
  the 
  deforested 
  

   area. 
  In 
  some 
  parts 
  of 
  the 
  State 
  of 
  New 
  York 
  these 
  differences 
  

   may 
  amount 
  to 
  as 
  much 
  as 
  5 
  or 
  6 
  inches 
  in 
  depth 
  over 
  the 
  entire 
  

   catchment 
  area. 
  Yet 
  it 
  must 
  be 
  said 
  that 
  this 
  proposition 
  is, 
  for 
  

   the 
  present, 
  tentative 
  in 
  its 
  character. 
  

  

  The 
  writer 
  is 
  particular 
  to 
  specify 
  dense 
  forests, 
  because 
  a 
  good 
  

   deal 
  of 
  discussion 
  has 
  clustered 
  around 
  this 
  point. 
  Of 
  such 
  for- 
  

   ests, 
  the 
  most 
  effective 
  are 
  those 
  composed 
  of 
  spruce, 
  pine, 
  and 
  

   other 
  evergreen 
  trees. 
  Where 
  the 
  forest 
  is 
  more 
  or 
  less 
  open 
  to 
  

   wind 
  and 
  sunshine, 
  its 
  effect, 
  while 
  considerable, 
  is 
  still 
  much 
  less 
  

   marked 
  than 
  that 
  of 
  dense 
  evergreen 
  forests 
  where 
  the 
  sun 
  seldom 
  

  

  