﻿438 
  F. 
  Waldo 
  — 
  Wind 
  Velocities 
  in 
  the 
  United 
  States. 
  

  

  For 
  the 
  Year, 
  the 
  maximum 
  curves 
  are 
  remarkably 
  sym- 
  

   metrical 
  and 
  have 
  an 
  absolute 
  maximum 
  at 
  about 
  15 
  h 
  , 
  and 
  

   while 
  the 
  amplitude 
  is 
  not 
  quite 
  so 
  great 
  as 
  for 
  July, 
  yet 
  the 
  

   period 
  during 
  which 
  the 
  curve 
  is 
  above 
  the 
  very 
  nearly 
  level 
  

   minimum 
  is 
  but 
  little 
  less 
  than 
  for 
  July, 
  and 
  what 
  shortening 
  

   there 
  is, 
  is 
  due 
  to 
  there 
  being 
  an 
  earlier 
  descent 
  to 
  the 
  mini- 
  

   mum 
  level. 
  The 
  time 
  of 
  minimum 
  is 
  still 
  in 
  the 
  early 
  

   morning 
  hours. 
  Secondary 
  phases 
  are 
  not 
  noticeable. 
  

  

  Lake 
  Region 
  (Curve 
  5). 
  — 
  On 
  the 
  Lower 
  Lakes 
  for 
  January, 
  

   the 
  curves 
  are 
  generally 
  very 
  irregular, 
  but 
  there 
  is, 
  in 
  every 
  

   case, 
  a 
  well 
  defined, 
  though 
  short, 
  principal 
  maximum 
  at 
  about 
  

   I4 
  h 
  . 
  The 
  time 
  of 
  the 
  principal 
  minimum 
  is 
  variable 
  ; 
  for 
  

   Rochester 
  and 
  Cleveland 
  it 
  occurs 
  only 
  about 
  four 
  or 
  five 
  

   hours 
  after 
  the 
  time 
  of 
  maximum, 
  consequently 
  at 
  about 
  18 
  h 
  , 
  

   and 
  for 
  Buffalo, 
  Detroit 
  and 
  Toledo 
  it 
  occurs 
  shortly 
  after 
  or 
  

   at 
  midnight. 
  Slight, 
  secondary 
  maxima 
  occur 
  for 
  Rochester 
  

   at 
  about 
  midnight 
  ; 
  for 
  Toledo 
  two 
  hours 
  earlier, 
  and 
  probably 
  

   for 
  Cleveland 
  at 
  about 
  23 
  h 
  . 
  

  

  For 
  July 
  a 
  fairly 
  well 
  rounded 
  maximum 
  culminates 
  at 
  14 
  h 
  , 
  

   but 
  the 
  time 
  of 
  minimum 
  is 
  by 
  no 
  means 
  regular, 
  for 
  it 
  occurs 
  

   at 
  about 
  4 
  hours 
  before 
  midnight 
  in 
  some 
  cases, 
  and 
  4 
  hours 
  

   after 
  midnight 
  in 
  others. 
  In 
  those 
  cases 
  in 
  which 
  the 
  

   maximum 
  is 
  the 
  best 
  developed, 
  the 
  minimum 
  occurs 
  after 
  

   midnight, 
  both 
  of 
  which 
  characteristics 
  belong 
  to 
  the 
  stations 
  

   having 
  greater 
  land 
  influence. 
  

  

  For 
  the 
  Year, 
  a 
  moderately 
  sized 
  maximum 
  with 
  gentle, 
  

   regularly 
  sloping, 
  sides 
  culminates 
  at 
  about 
  I4 
  h 
  . 
  The 
  minimum 
  

   period 
  covers 
  about 
  half 
  the 
  twenty-four 
  hours, 
  and 
  the 
  abso- 
  

   lute 
  minimum 
  follows 
  closely 
  the 
  relations 
  just 
  given 
  for 
  July, 
  

   but 
  the 
  absolute 
  change 
  is 
  so 
  much 
  smaller 
  than 
  for 
  that 
  

   month 
  that 
  the 
  whole 
  minimum 
  period 
  varies 
  but 
  little 
  from 
  

   a 
  fixed 
  level. 
  

  

  For 
  the 
  Upper 
  Lakes 
  for 
  January 
  there 
  is 
  a 
  principal 
  

   maximum 
  at 
  times 
  varying 
  from 
  12 
  h 
  to 
  15 
  h 
  and 
  the 
  crest 
  is 
  

   the 
  more 
  pointed, 
  the 
  better 
  the 
  water 
  exposure. 
  While 
  the 
  

   principal 
  minimum 
  occurs 
  in 
  the 
  early 
  morning 
  hours 
  (4 
  h 
  and 
  

   8 
  h 
  ) 
  for 
  most 
  of 
  the 
  stations, 
  yet 
  at 
  Duluth 
  a 
  secondary 
  mini- 
  

   mum 
  occurs 
  at 
  17 
  h 
  or 
  18 
  h 
  , 
  and 
  this 
  is 
  of 
  the 
  same 
  magnitude 
  

   as 
  the 
  primary. 
  The 
  minimum 
  period 
  is 
  very 
  irregular 
  and 
  

   broken 
  in 
  all 
  cases, 
  and 
  there 
  are 
  traces 
  of 
  secondary 
  phe- 
  

   nomena, 
  which 
  are 
  well 
  marked 
  only 
  in 
  the 
  case 
  of 
  Duluth, 
  

   where 
  the 
  maximum 
  nearly 
  equal 
  to 
  the 
  primary 
  occurs 
  

   near, 
  or 
  shortly 
  before, 
  midnight, 
  and 
  the 
  minimum 
  as 
  just 
  

   mentioned. 
  

  

  For 
  July 
  there 
  is 
  a 
  well 
  marked, 
  rather 
  rounded 
  maximum 
  

   at 
  15 
  h 
  in 
  most 
  cases, 
  but 
  at 
  14 
  h 
  at 
  Alpena, 
  with 
  minimum 
  at 
  

   about 
  3 
  h 
  for 
  Alpena 
  and 
  Chicago, 
  but 
  with 
  the 
  principal 
  

   minimum 
  just 
  before 
  and 
  at 
  midnight 
  at 
  Milwaukee 
  and 
  

  

  