1904-5.] Rainfall Records in the Talla Drainage Area. 635 
Monthly Distribution of Rainfall. 
Rainfall stated as hundredth parts of total Rainfall in 
particular Year. 
1896 
1897 
1898 
1899 
1900 
1901 
1902 
Average of 
7 years. 
Maximum 
above Average 
Minimum 
below Average. 
Jan. 
6-1 
3-3 
6-8 
10-4 
8-8 
6-5 
10-5 
7-4 
3-1 
4-1 
Feb. 
6‘7 
8*3 
6-7 
9-6 
4-1 
4-4 
3-9 
6-4 
3-2 
2-5 
Mar. 
11-4 
11-9 
3-1 
9-0 
1-1 
5‘7 
7-5 
7-1 
4-8 
6-0 
Apr. 
4-0 
6-6 
10-4 
8-0 
4-9 
9-8 
8-5 
7-3 
3-1 
3-3 
May 
1-3 
4-7 
4-6 
7'0 
8-9 
5*1 
5-6 
5*4 
3-5 
4*1 
June 
9-4 
6-8 
6-4 
3-2 
10-6 
9*4 
3-3 
7-1 
3-5 
3-9 
July 
11 *6 
5-8 
2-9 
7-7 
6*5 
3’1 
7-4 
6-4 
5-2 
3-5 
Aug. 
6*2 
14-8 
10-7 
3-8 
8-7 
12-7 
7-1 
9-3 
5-5 
5*5 
Sept. 
14-3 
6-4 
9-1 
8-8 
8-2 
14-1 
8-3 
9-7 
4-6 
3-3 
Oct. 
9*8 
6-5 
12-1 
8-7 
9-9 
12-5 
9-1 
9-6 
2-9 
3-1 
Nov. 
4*2 
7-8 
11-8 
19-3 
8-9 
7-5 
12-6 
10-3 
9-0 
6-1 
Dec. 
15-0 
17-1 
15-4 
4-5 
19-4 
9-2 
16-2 
14-0 
5-4 
9-5 
100-0 
100-0 
100-0 
100-0 
100-0 
100-0 
100-0 
100-0 
The question of the monthly distribution of the rainfall is of 
practical importance in the determination of the reservoir storage 
required to be provided in order that a uniform daily supply of 
water, based on a figure of annual rainfall, may he regularly 
maintained. In the present case, the minimum daily yield of the 
drainage area having been based upon an annual rainfall (as 
recorded in rain-gauges) of 53 inches, a minimum monthly rainfall 
of 4*42 inches and a daily rainfall of *145 inches is required in 
order that this yield may be obtained without the provision of 
reservoir storage, assuming for the moment that the rate of loss 
by evaporation, etc. remains constant throughout the year. 
The total annual requirement of 53 inches of rainfall was ex- 
ceeded in 6 years out of the 7 under review ; hut of these 6 years, 
there were 3 in which for 6 months the monthly requirement 
of 4*42 inches was not obtained ; 2 years in which there was 
a shortage during 3 months ; and in the year with the 
maximum rainfall of 76*47 inches, the rainfall was less than 4 '42 
