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■ Hungry grounds require to have the cause well looked into (the waterturned as above directed) or if in want, such as is well enriched.
Lands that are hot and burning, allay with swines’ dung (as some say)the coldest; or with neat’s, which will certainly refresh it..
bat the width at the bottom must be regulated by the nature and size of the materialsintended to be used. If the drain is to be made of bricks ten inches long, three inchesthick, and four inches in breadth, then the bottom of the drain must be twelve inches;but if the common sale bricks are used, then the bottom must be proportionably contracted.In bosh cases there must be an interstice of one inch between the bottom brick and tliesides of the trench, and the vacuity must be filled up with straw, rushes, or loose mould.For the purpose of making these drains, I order my bricks to be moulded ten inches long,,four broad, and three thick. These dimensions make the best drain; and I beg leave tobe understood, throughout this efsay, as speaking of bricks formed in the above manner.
“ The method I pursue in constructing my main drains is as follows:
“ When the ground is soft and spying)', the bottom of the drain is laid with bricks placedacrofs. On these, on each side, two bricks are laid flat, one upon the other, forming adrain six inches high and four broad. This is covered with bricks laid flat. Fig. 2. Plate 1.
“ When 1 first engaged in this mode of draining, I conceived that in places where thebottoms of the main drains were firm and solid, as of day or marl, it would be an unne-cefsary expence to pave them with brick. Under this idea, I recommended them to beconstructed as in plate 1 , fig. 3. the sides being formed by placing- one brick edgeways,instead of two laid flat. Bud after the experience of some years, I found, that the accefsof air, and the alternation of wet and dry, occasioned the hardest clay or marl to crumbledown, whereby the side bricks, not having a paved bottom, were made to fall in. Fromthe experience of this circumstance, I now direct the main drains to be invariably pavedwith brick, as represented in plate l. fig. 2. ■ This will render them as lasting as the sod,or pipe drains, which I have found free and open after being constructed twenty five years.
« When stones are used instead of bricks, the bottom of the drain should be about eight,inches in width. And here it will be proper to remark that, in all cases, the bottom ofthe main drains must be sunk four inches below the level of the narrow ones, even at thepoint where the latter fall into them.
“ The main drains should be kept open till the narrow ones are begun from them, afterwhich they may be finished: but before the earth is returned upon the stones or bricks, itwill be adviseable to throw in straw, rushes, or brush-wood, to increase the freedom ofthe drain.
“ The small narrow drains should be cut at the distance of sixteen or eighteen feet from,each other, and should fall into the main drain at very acute angles, to prevent any stop-page. At the point where they fall into, and eight or ten inches above it, they should bemade firm with brick or stone.
“ In making the narrow drains I employ four labourers, The first man, with a common
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