MONTH.

Table of the average monthly and yearly heights of water in the Lake above the bottom of the Aqueduct.

1851. 1852. 1853. 1854, 1855. 1856. 1857. 1858. 1859.* 1860. | 1861. | 1862. | 1863. 1864. 1865. 1866. 1867. 1868. 1869, 1870.

January

April

May

June

July

August

7.29 10.97 11.02 9.85

9.50 10.63 9.51 10.54 10.16 8.06 9.53 10.75 10.80 10.83 11.93 6.09 11.33 13.88 7.41
February 10.21 10.20 10.78 10.95 10.65 7.59 10.28 10.05 12.17 11.36 12.77 6.57 12.85 13.71 8.24
March
10.43 10.49 10.44 10.93 10.68 6.96 10.67 9.35 12.45 12.67 13.21 8.65 13.95 14.33 12.28
11.17 11.23 10.68 10.66 11.57 10.24 12.30 9.36 12.06 12.72 14.14 12.40 14.59
11.02 10.94 10.98 10.87 11.35 12.05 12.05 10.67 12.06 11.52 13.88 14.45 14.01
10.40 10.28 10.62 10.33 10.69 11.78 12.14 11.72 11.96 10.83 12.99 14.43 13.29
9.76 9.44 9.45 9.00 9.86 10.67 11.41 11.74 10.22 10.42 11.50 14.05 12.82
9.01 8.40 8.64 6.67 9.01 11.59 11.70 11.30 10.24 9.42 10.27 12.97 13.73
September. 8.00 5.68 7.78 6.64 7.52 10.82 11.72 10.40 9.84 9.42 8.71 11.33 13.43 7.91
October
7.55 6.55 7.34 5.90 6.42 10.10 11.10 8.72 10.15 10.35 7.79 10.30 12.94
November 8.07 7.74 9.58 6.09 6.28 10.80 11.16 9.01 9.98
December 9.67 8.49 10.57 8.38
10.54

14.32 14.00

14.26

14.00

12.01 13.44

13.51

13.41

13.67
12.72 13.20 13.37

8.37 12.14 10.29
8.73 13.14 9.75
10.58 13.57 10.96
11.96 13.50 13.29 13.40
13.65

12.27 13.25

12.96 13.19

13.21 12.81 13.33

13.12

18.23 13.02

Table showing the Rainfall in Boston for the year 1870, and the days on which it occurred, from observations by Wm. H. Bradley, Esq., Superintendent of Sewers.

Day of Month.

MONTHS.

Jan. Feb. Mar. Apr. May. June. July. Aug. Sept. Oct. Nov. Dec.

Annual Amount of Rainfall, in Inches, at Lake Cochituate, Boston and vicinity, 1849 to 1870, inclusive.

CONDUIT AT THE LAKE.

The following table shows the varying depths of the water in the conduit at the gate-house, the number of days in each month that the water was running at those depths, and the average depth for each month.

Depths Jan. Feb. Mar. April. May. | June. July. Aug. Sept. Oct. Nov. Dec. Tot'l Ft. In. Days. Days. Days. Days. Days. Days. Days. | Days. Days. Days. Days. Days. Dys.

Average Monthly Depths.

Average Monthly and Yearly Heights, in feet and decimals, of the Water in the Brookline, Beacon Hill, South and East
Boston Reservoirs, above" tide marsh level," 1861-70.

1864. 1865. 1866. | 1865. 1866. 1867. 1868. 1869. 1870. 1861. 1862. 1863, 1864. 1865. 1866. 1867. 1868. 1869. 1870.

|

1864.

118.63

118.34

|
| |
122.81 122.46 123.64 122.37 123.31 122.28 122.00 | 123.29 122.58 | 122.83
122.68 122.85 123.23 122.61 122.82 | 122.47 123.12 122.79 122.64 122.60
123.32 123.52 | 123.23 | 123.62 | 123.26 | 123.19 123.05 122.33 122.48 | 122.77
124.01 | 124.18 123.85 | 123.82 | 123.38 | 123.45 | 123.00 | 123.04 | 122.60 | 122.56
124.04 124.00 123.52 | 123.62 | 122.65 | 123.04 123.07 123.04 122.77 | 122.75
123.68 123.25 123.17 122.66 123.23 123.29 122.34 122.77 121.85 122.64
122.68 123.73 | 122.76 | 122.87 | 123.33 | 122.97 122.98 122.77 | 122.10 122.50
123.71 123.70 123.11 | 122.64 | 123.39 122.80 122.23 122.75 | 122.19 | 122.23
123.76 123.64 123.36 122.03 123.29 122.81 122.52 122.12 122.50 122.35
| |
113.14 116.22 116.12 115.91 119.03 119.39 120.46 118.20 117.45
123.79 123.85 122.26 123.19 123.29 123.03 122.65 122.31 122.58 122.64 115.91
115.87 118.17 118.43 119.50 | 120.46 | 118.61 118.36
123.80 | 124.07 | 123.63 | 122.78 | 123.38 | 122.75 | 122.89 | 122.56 | 122.46 122.60 116.74 117.20 116.85
124.00 | 123.46 | 122.53 | 122.29 | 123.24 | 122.64 | 122.37122.00 122.92 | 122.50
122.50 | |
|
117.45 115.23 118.30 117.35 120.50 119.37 120.02 117.78 118.36

116.61 117.48 118.36 117.72 119.18 | 119.20 119.11 120.20 118.51
118.93 119.46 118.18 117.54 | 118.91 119.65 118.59 120.11 118.72 117.78
119.05 119.18 118.03 | 116.38 | 120.58 | 120.72 | 119.45 | 120.57 | 118.30 118.07
118.91 117.91 117.27 | 117.21 | 121.28 | 120.70 119.86 120.57 | 118.82
119.06 117.59 116.33 116.53 | 120.31 | 119.53 118.50 118.65 119.68
117.32 116.39 | 115.40 | 115.31 120.56 118.53 | 118.34 | 118.45 | 117.13
| |
116.48 116.46 116.34 115.32 121.23 119.51 119.00 120.24 117.20
114.18 116.22 116.05 115.19 119.83 119.17 117.70 117.11 117.63

118.63

118.03

119.30

119.59

117.72

117.80

118.55 | | | 120.14 119.78 120.84 119.03 118.45

118.61

119.38

Yearly Av'ge | 123.52 123.56 123.19 | 122.87 123.21 122.89 122.69 122.65 122.48 122.58

1 | | |

116.98 117.21 116.92 116.77 120.00 119.59 119.36 119.11 118.13 118.49