﻿HYDROLOGY 
  OP 
  NEW 
  YORK 
  341 
  

  

  mean 
  annual 
  rainfall 
  at 
  Oxford 
  for 
  the 
  same 
  period 
  was 
  27.30 
  

   inches, 
  and 
  the 
  mean 
  annual 
  temperature, 
  48.5° 
  Fahr. 
  We 
  have, 
  

   therefore, 
  3.54 
  inches 
  less 
  mean 
  annual 
  evaporation, 
  as 
  measured 
  

   in 
  the 
  catchment 
  of 
  the 
  Thames, 
  than 
  at 
  Hemlock 
  lake. 
  

  

  During 
  the 
  ten-year 
  period, 
  1893-1902, 
  inclusive, 
  the 
  mean 
  run- 
  

   off 
  of 
  the 
  river 
  Thamas 
  was 
  only 
  7.29 
  inches, 
  instead 
  of 
  8.49 
  

   inches, 
  as 
  in 
  the 
  previous 
  ten-year 
  period. 
  In 
  consideration 
  of 
  

   the 
  showing 
  made 
  of 
  the 
  low 
  runoffs 
  of 
  streams 
  in 
  the 
  State 
  of 
  

   New 
  York, 
  it 
  is 
  probable 
  that 
  when 
  a 
  complete 
  computation 
  of 
  

   the 
  runoff 
  of 
  Hemlock 
  lake 
  is 
  made, 
  it 
  will 
  be 
  found 
  to 
  be 
  some- 
  

   what 
  less 
  than 
  that 
  of 
  the 
  Thames 
  in 
  England. 
  1 
  

  

  Geologically 
  the 
  Hemlock 
  lake 
  catchment 
  is 
  in 
  the 
  Hamilton 
  

   and 
  Marcellus 
  shale, 
  with 
  the 
  hills 
  at 
  the 
  sides 
  rising 
  to 
  the 
  rocks 
  

   of 
  the 
  Portage 
  group. 
  

  

  Discharge 
  measurements 
  of 
  Oswego 
  river. 
  The 
  following 
  record 
  

   of 
  Oswego 
  river 
  is 
  taken 
  daily, 
  with 
  the 
  exception 
  of 
  Sundays 
  and 
  

   holidays. 
  

  

  These 
  gagings 
  are 
  made 
  at 
  the 
  State 
  dam, 
  three 
  miles 
  from 
  

   Lake 
  Ontario, 
  with 
  an 
  effective 
  head 
  at 
  the 
  dam 
  of 
  about 
  32 
  feet. 
  

   This 
  dam 
  is 
  of 
  masonry, 
  with 
  its 
  crest 
  365.5 
  feet 
  long. 
  Flash- 
  

   boards 
  are 
  maintained 
  during 
  the 
  greater 
  part 
  of 
  the 
  year. 
  In 
  

   estimating 
  the 
  flow, 
  when 
  flashboards 
  are 
  removed, 
  a 
  discharge 
  

   curve 
  has 
  been 
  prepared 
  using 
  coefficients 
  in 
  the 
  weir 
  formula, 
  

   as 
  per 
  Cornell 
  experiment 
  No. 
  3, 
  given 
  in 
  the 
  paper 
  On 
  the 
  Flow 
  

   of 
  Water 
  Over 
  Dams. 
  

  

  It 
  is 
  possible 
  that 
  the 
  records 
  are 
  somewhat 
  too 
  small, 
  owing 
  

   to 
  leakage 
  and 
  settlement 
  of 
  the 
  dam. 
  A 
  headrace 
  sup- 
  

   plies 
  water 
  to 
  an 
  electric-light 
  plant 
  and 
  the 
  Oswego 
  water 
  works 
  

   pumping 
  station. 
  There 
  are 
  eight 
  water 
  wheels 
  in 
  use. 
  The 
  

   amount 
  of 
  water 
  passed 
  through 
  these 
  wheels 
  varies 
  from 
  300 
  

   cubic 
  feet 
  per 
  second 
  to 
  about 
  650 
  cubic 
  feet 
  per 
  second. 
  In 
  the 
  

  

  i 
  Discussion 
  of 
  the 
  flow 
  of 
  the 
  river 
  Thames 
  from 
  1883-1892, 
  may 
  be 
  

   found 
  in 
  (1) 
  the 
  Report 
  on 
  the 
  Flow 
  of 
  the 
  Thames, 
  by 
  A. 
  R. 
  Binnie, 
  

   Chief 
  Engineer 
  to 
  the 
  London 
  County 
  Council— 
  a 
  publication 
  of 
  the 
  Coun- 
  

   cil, 
  1892; 
  and 
  (2) 
  a 
  Report 
  on 
  the 
  Shrinkage 
  of 
  the 
  Thames 
  and 
  Lea, 
  by 
  

   Maurice 
  Fitz 
  Maurice, 
  Chief 
  Engineer--a 
  publication 
  of 
  the 
  London 
  

   County 
  Council, 
  presented 
  to 
  the 
  Water 
  Committee 
  on 
  February 
  10, 
  1903. 
  

  

  