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Irrigation and the Storage of Water 
a small quantity by the stream running from Hanstead Norris 
to Pangbourne. These are usually fed off in the spring from 
April to May with sheep, being let for 31. or 4£. per acre for the 
feed — in some backward seasons they make more. They are 
watered from the middle of May to about the middle of July 
and afterwards fed up to the end of November by cattle and 
horses. 
The Storage of Water. 
One inch of rainfall represents, as is well known, 100 tons 
of water per acre, and the average annual rainfall of England 
varies from about 20 to 25 inches on the East Coast to 40, 60, 
and even 80 inches or more on the Western Hills and the West 
Coast generally. If 30 inches be taken as the average down- 
fall, this would be equivalent to 3,000 tons per acre, a quantity 
equal to about 13,000 hogsheads of water. An immense portion 
of this rainfall runs to waste, some authorities being of opinion 
that it amounts to as much as nine-tenths. Why should not 
a large quantity of it be stored in reservoirs at hill-sides, the 
drainage water of farms, ditches, and brooks being intercepted 
and made to fill them before it reaches valleys and lowlands ? 
This idea recommended itself to Mr. Pitt before the present 
century commenced, and he says in his survey of Staffordshire : — 
The gTeat desideratum in this species of improvement seems to be the 
introduction of reservoirs constructed so as to contain large quantities of flood 
water, which may be successively and at pleasure distributed upon any lapd 
below its surface. This idea as applicable to agriculture is, I believe, novel, 
and may be treated as visionary ; but I am so thoroughly convinced of the 
great advantages to be derived from it that I will venture a prediction of its 
being in some future time practised to a great extent. 
Mountain torrents are by no means so considerable in the 
greater part of England as in Ireland, but there are hill-sides 
and plains everywhere which might be profitably irrigated by 
the drainage water, running in ditches from higher lands, being 
intercepted and stored in reservoirs or catchponds, as they are 
termed in the West of England. As the construction of these 
is a matter attended with expense, it is important to con- 
sider what this would be. The late Mr. Bailey Denton in a 
lecture on water storage, delivered some years since, calcu- 
lated that a reservoir to hold 720,000 gallons would require 
four- tenths of an acre to be excavated at a depth of feet, 
and that the cost of excavating and putting the earth round 
to form a bank would be 62 1. 10s., the calculation being that 
it would be 2,500 yards at 3d. per yard. If the bottom of the 
pond had to be puddled, the cost would be considerably 
