﻿HYDROLOGY 
  OF 
  NEW 
  YORK 
  

  

  843 
  

  

  Table 
  No. 
  97 
  comprises 
  the 
  averages 
  of 
  the 
  regular 
  weekly 
  sani- 
  

   tary 
  analyses, 
  as 
  made 
  for 
  the 
  Health 
  Department 
  of 
  Rochester 
  by 
  

   Fred 
  R. 
  Eilinger 
  : 
  

  

  Table 
  No. 
  97. 
  — 
  Analyses 
  of 
  hemlock 
  lake 
  water 
  for 
  1902 
  

   (Parts 
  per 
  100,000) 
  

  

  Month 
  

  

  (1) 
  

  

  January 
  . 
  . 
  . 
  

   February 
  . 
  

   March 
  .... 
  

  

  April 
  

  

  May 
  

  

  June 
  

  

  July 
  

  

  August 
  . 
  . 
  . 
  

   September 
  

   October 
  . 
  . 
  . 
  

   November 
  . 
  

   December 
  

  

  Average 
  

  

  Oh 
  

  

  111 
  

  

  (2) 
  

  

  %2 
  

  

  ■2 
  ° 
  

  

  (3) 
  I 
  (4) 
  (5) 
  

  

  9.875 
  

   4). 
  500 
  

   9.500 
  

   9.125 
  

   9.125; 
  

   9.875 
  1 
  

   10.666: 
  

   10.125 
  

   9.750 
  

   9.125 
  ! 
  

   9.1251 
  

   9.250! 
  

  

  6.375 
  

   5.875 
  

   6.000 
  

   5.750 
  

   6.000 
  

   5.875 
  

   6.666 
  

   6.437 
  

   6.250 
  

   5.375 
  

   6.125 
  

   5.875 
  

  

  .1902 
  

   .1901! 
  

  

  9.586 
  6.050 
  

   9.833 
  6.239 
  

  

  3.500 
  

   3.625 
  

   3.500 
  

   3.3751 
  

   3.125 
  

   4.000 
  

   4.000 
  

   3.687 
  

   3.500 
  

   3.750 
  

   3.000 
  

   3.375 
  

  

  3.536 
  

   3.594 
  

  

  0.0010 
  

   0.0010 
  

   0.0010 
  

   0.0010 
  

   0.0010 
  

   0.0010 
  

   0.0010 
  

   0.0011 
  

   0.0010 
  

   0.0011 
  

   0.0010 
  

   0.0020 
  

  

  0.0011 
  

   0.0010 
  

  

  (6) 
  

  

  0092 
  

   0081 
  

   0087 
  

   0087 
  

   0091 
  

   0091 
  

   0091 
  

   0090 
  

   0090 
  

   0086 
  

   0086 
  

   0088 
  

  

  (?) 
  

  

  

  •G 
  

  

  a'S 
  

  

  a 
  

  

  0> 
  

  

  (8) 
  

  

  0.2200 
  

   0.2200 
  

   0.2175 
  

   . 
  22001 
  

   0.2225 
  

   0.2275 
  

   0.2200 
  

   0.2200 
  

   0.2150 
  

   0.2150 
  

   0.2175 
  

   0.2175 
  

  

  Trace 
  

  

  0.0088 
  

   0.0089 
  

  

  0.2177 
  

   0.0221 
  

  

  (9) 
  

  

  None 
  

  

  Hardness 
  is 
  not 
  ordinarily 
  determined 
  because 
  it 
  does 
  not 
  vary 
  

   much, 
  being 
  nearly 
  constant 
  from 
  year 
  to 
  year. 
  The 
  following 
  by 
  

   Mr 
  Eilinger 
  shows 
  the 
  small 
  variation: 
  

  

  Total 
  hardness, 
  parts 
  per 
  100,000 
  

  

  December 
  7, 
  1895 
  6.70 
  

  

  December 
  21, 
  1895 
  6.70 
  

  

  January 
  18, 
  1896 
  6.20 
  

  

  February 
  1, 
  1896 
  6.80 
  

  

  April 
  10, 
  1897 
  : 
  6.20 
  

  

  May 
  8, 
  1897 
  6.80 
  

  

  July 
  9, 
  1898 
  7.30 
  

  

  June 
  19, 
  1903 
  6.80 
  

  

  June 
  10, 
  1904 
  6.70 
  

  

  