If this first catch-water is to be employed at any time as a flooder, the upper edge of its bank must be carefully trimmed to the level; but I believe, on the whole, it will be more advisable to make a separate flooder immediately below, which may be cut at the exact level by means of the plumb rule, to the depth of one, and width of two feet; with an outlet from the catch-water at every five or ten Irish chains.
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