09 
From the foregoing table it will be seen that Mr. 
Walker’s mean yearly average of 8 years, was 
That including Mr. Walker’s, the mean yearly \ 35.3988 
average of 72 years, w'as i 
That excluding Mr. Walker’s, the mean year 
average of 64 years, w'as 
That Dr. Dalton’s mean yearly average of 47 \ 35.523 
years, was J 
Showing the small difference of *039 between the two latter 
averages. 
Mr. Curtis thinks it may be assumed that Dr. Dalton was 
correct in supposing Mr. Walker’s returns were in excess of 
the reality ; and for the purpose of arriving at a correct 
average, it will be safer to omit them and adopt 35‘562 as the 
average fall of rain for Manchester. 
The table also shows that, taking the average, April is the 
driest and October the wettest month in the year. That the 
fall of rain in the first 6 months of the year, is to that of the 
last 6 months as 2 to 3. That there is less difference 
between the two periods in the later returns than in the 
earlier ones. Whether this progressive diminution of differ- 
ence between the first and last half of the year is owing to 
the later returns being for shorter periods, or to some change 
in the fall of rain, influenced by a change of circumstances, he 
left for future returns to show. 
The following table shows the greatest and least amount of 
rain which has fallen in every month during the 72 years, 
with the year in which it fell, and the name of the collector. 
January ... 
180(i 
Inchc.s. 
5-851 
Dalton 
18.53, 1838 
Inches. 
0-320 
Dalton 
February .. 
1848 
6-665 
Casartelli 
1800 
0-440 
Dalton 
March 
1827 
C-030 
Dalton 
1808, 1820 
0-180 
Dalton 
April 
1701 
4-750 
Walker 
1842 
0 1(!0 
Casartelli 
Mav 
1792 
8.000 
Walker 
IK44 
0-090 
Casartelli 
June 
1800 
7-05.5 
Dalton 
18-26 
0-200 
Dalton 
July 
1828 
11-480 
Dalton 
1800 
0-290 
Dalton 
August ... 
1790 
8-740 
Dalton 
1801 
0-730 
Dalton 
September 
1792 
9-000 
Walker 
1804 
0-240 
Dalton 
October ... 
1787 
0-000 
Walker 
1817 
0-(l04 
Dalton 
November. 
1 82.5 
7 -.‘1 7 5 
Dalton 
1805 
0-624 
Dalton 
December. 
1792 
9-500 
Walker 
1844 
0-070 
Casartelli 
n 
35-5620 
I 43-0922 
