﻿338 
  

  

  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  of 
  the 
  lake; 
  (2) 
  at 
  an 
  artificial 
  channel 
  through 
  which 
  water 
  was 
  

   discharged 
  at 
  will 
  for 
  the 
  benefit 
  of 
  the 
  millers 
  on 
  the 
  outlet; 
  

   and 
  (3) 
  through 
  the 
  conduit 
  of 
  the 
  Eochester 
  Waterworks. 
  The 
  

   runoffs 
  given 
  are 
  the 
  sums 
  of 
  these 
  several 
  outgoes. 
  In 
  order 
  to 
  

   determine 
  the 
  outflow 
  of 
  the 
  natural 
  outlet, 
  a 
  weir 
  was 
  con- 
  

   structed 
  and 
  the 
  discharge 
  observed 
  at 
  different 
  bights 
  of 
  the 
  

   lake 
  surface. 
  The 
  discharge 
  into 
  the 
  artificial 
  channel 
  was 
  

   through 
  submerged 
  orifices 
  of 
  known 
  dimensions, 
  and 
  has 
  been 
  

   computed 
  from 
  standard 
  formulas 
  for 
  the 
  discharge 
  of 
  such 
  ori- 
  

   fices, 
  the 
  size 
  of 
  the 
  openings 
  and 
  the 
  difference 
  of 
  level 
  of 
  water 
  

   surfaces 
  above 
  and 
  below 
  being 
  known. 
  

  

  The 
  discharge 
  of 
  the 
  conduit 
  of 
  the 
  Rochester 
  Waterworks 
  is 
  

   as 
  computed 
  from 
  standard 
  formulas 
  for 
  discharge 
  through 
  

   pipes. 
  Measurements 
  made 
  by 
  the 
  writer 
  and 
  others 
  during 
  the 
  

   last 
  few 
  years 
  show 
  that 
  the 
  computed 
  quantities 
  passing 
  

   through 
  the 
  conduit 
  were 
  not 
  far 
  from 
  correct. 
  

  

  Table 
  No. 
  49 
  — 
  Water 
  pbawn 
  from 
  Hemlock 
  lake 
  for 
  the 
  water 
  years 
  

  

  1880 
  to 
  1884, 
  inclusive 
  

  

  [In 
  inches 
  on 
  the 
  catchment] 
  

  

  

  1880 
  

  

  1881 
  

  

  MONTH 
  

  

  c3 
  © 
  

  

  "© 
  £h 
  

  

  Is 
  

   si 
  

  

  3 
  

   a 
  

  

  CI 
  

  

  eg 
  

  

  u 
  

  

  1 
  

  

  a 
  

  

  ©^ 
  

   -a 
  u 
  

  

  +-* 
  © 
  

  

  a 
  

   1 
  

  

  e 
  

  

  a> 
  

  

  s 
  

  

  s 
  

  

  53 
  © 
  

  

  >% 
  

   © 
  .» 
  

  

  ©"£ 
  

  

  2 
  © 
  

  

  a 
  a 
  

  

  S'S 
  

  

  J 
  -43 
  

   3 
  

  

  e3 
  

  

  d 
  

  

  '3 
  

  

  a 
  

   u 
  

   ■a 
  

  

  u 
  

   © 
  

  

  1 
  

  

  It 
  

  

  "3 
  

  

  ■3 
  

   P3 
  

  

  s 
  

  

  c3 
  

   s- 
  

  

  e 
  

  

  (1) 
  

  

  (2) 
  

  

  —1.67 
  

   —0.91 
  

   —0.11 
  

  

  (3) 
  

  

  1.26 
  

   1.37 
  

   1.45 
  

   1.47 
  

   1.25 
  

   2.08 
  

  

  (4) 
  

  

  (5) 
  

  

  (6) 
  

  

  (2) 
  

  

  (3) 
  

  

  (4) 
  

  

  (5) 
  

  

  (6) 
  

  

  December 
  

  

  0.16 
  

   0.15 
  

   0.16 
  

   0.15 
  

   0.15 
  

   0.17 
  

  

  

  a31.4 
  

   a25.5 
  

   a27.3 
  

   a31.8 
  

   a45.7 
  

   71.8 
  

  

  -1.33 
  

   —1.47 
  

   -0.11 
  

   +1.20 
  

  

  +1.47 
  

   +1.32 
  

  

  0.72 
  

   2.24 
  

   1.08 
  

   1.92 
  

   0.52 
  

   2.23 
  

  

  0.49 
  

   0.44 
  

   0.54 
  

   1.73 
  

   1.24 
  

   1.11 
  

  

  

  27.3 
  

  

  

  24.7 
  

  

  February 
  

  

  29.7 
  

  

  

  +0.21 
  

   +0.79 
  

  

  +0.87 
  

  

  39.1 
  

  

  April 
  

  

  45.2 
  

  

  May 
  

  

  69.7 
  

  

  

  

  Storage 
  period 
  

  

  -0.14 
  

  

  8.88 
  

  

  0.94 
  

  

  7.94 
  

  

  38.9 
  

  

  +0.18 
  

  

  8.71 
  

  

  5.55 
  

  

  3.16 
  

  

  39.3 
  

  

  

  

  

  +0.45 
  

   —0.15 
  

   -0.70 
  

  

  1.66 
  

   1.93 
  

   3.46 
  

  

  0.36 
  

   0.41 
  

   0.35 
  

  

  

  76.5 
  

  

  77.1 
  

   74.4 
  

  

  +1.08 
  

   +0.58 
  

  

  3.13 
  

   3.71 
  

   0.95 
  

  

  0.76 
  

   0.43 
  

   0.50 
  

  

  6.10 
  

  

  73.9 
  

  

  July 
  

  

  75.0 
  

  

  

  80.0 
  

  

  

  

  

  -0.13 
  

  

  7.05 
  

  

  1.12 
  

  

  5.93 
  

  

  76.0 
  

  

  +0.55 
  

  

  7.79 
  

  

  1.69 
  

  

  76.5 
  

  

  

  

  

  —1.13 
  

   -1.57 
  

   —1.24 
  

  

  1.35 
  

   3.85 
  

   0.86 
  

  

  0.31 
  

   0.31 
  

   0.39 
  

  

  

  69.7 
  

   53.4 
  

   37.1 
  

  

  -0.69 
  

   -0.81 
  

   —0.71 
  

  

  1.73 
  

   4.23 
  

   1.81 
  

  

  0.35 
  

   0.33 
  

   0.46 
  

  

  

  77.9 
  

  

  

  59.1 
  

  

  

  44.8 
  

  

  

  

  

  -1.81 
  

  

  6.06 
  

  

  1.01 
  

  

  5.05 
  

  

  53.4 
  

  

  -0.74 
  

  

  7.77 
  

  

  1.14 
  

  

  6.63 
  

  

  60.6 
  

  

  

  

  Yearly 
  mean 
  or 
  total 
  

  

  —0.43 
  

  

  21.99 
  

  

  l 
  

  

  3.07 
  

  

  18.92 
  

  

  61.8 
  

  

  +0.04 
  

  

  24.27 
  

  

  8.38 
  

  

  15.89 
  53.9 
  

  

  alnterpolated 
  from 
  average 
  of 
  fifteen 
  years 
  

  

  