The ground, where not naturally dry, ought to be perfectly under- drained, by drains down the middle of both the front and back gardens, communicating with the public sewer, or with some other main drain; or, if the back garden be large, and the soil very wet, there may be a drain along one side of each of the tide walks: to these drains there ought to be communications, with gratings at regular distances, if the walks are above 100 ft. in length; hut, if they are shorter, one grating, in the lowest part of the garden, will he sufficient If the garden be 50 ft. or 60 ft. broad, the soil a very strong clay, and the surface flat, there ought not only to be drains to the walks, but drains to the part of the garden kept under kitchen crops or flowers, and also to those parts which are kept under grass. Nothing contributes more to the comfort afforded by a garden on a strong clayey soil, than thorough drainage; without which it is impossible to walk out in it after a shower of rain, though this is generally one of the most delightful times in which a garden can be viewed by a person fond of gardening.

In very small gardens, where it is not considered necessary to have under-drains, it will be sufficient to direct the water by the surface-drainage to one point, where it may sink into the soil. The proper execution of the surface-drainage is of the utmost importance to the enjoyment of every description of garden, whether large or small; more especially of all such as are on loamy or clayey soils. For this reason, even, in some cases, before determining on the under-drainage of the back garden, the surface-drainage ought to be attended to by smoothing down all the inequalities of the ground, and by forming it so as to give it an inclination, or slope, to some one part in the garden, generally that which is the most distant from the house. To this point all the rain water that falls on the walks should run, and find an exit either by a porous subsoil, or by a grating communicating with an under-drain. In back gardens of great length, it may happen that the middle is the lowest part of the surface; and when this is the case, the surface water ought to be directed thither from both extremities; but in suburban gardens it seldom happens that the surface may not be made to slope from the house to the extreme end of the hack garden, even though it should be 200 ft. in length.

In regard to front gardens, if the walk and the lawn have an inclination from the house to the street, that will generally be found sufficient. The surface-drainage, and also the under drainage, being determined on in the mind of the artist, we shall suppose that he has had the surface of the ground, both before and behind the house, sloped accordingly. The next point is to determine the number and direction of the walks; because it is alongside of them that the under-drains are commonly formed with the greatest advantage. In all small gardens, the object is to get as long a walk as possible; and the longest line within any given space must necessarily be that which goes round it. The direction and position of the walks is therefore easily settled. The next point is to determine where the drains are to be placed, and to have them dug and filled in, the manner of doing which will be treated of under the head of garden operations. The walks may be then hollowed out, in the manner which will also be hereafter described; and the ground which is to be planted or covered with turf may be trenched to the depth of 2 ft. or 3ft.; and, in performing this operation, if the soil requires to be rendered lighter, or more porous, which is always the case with a strong clay, it ought to be mixed with lime rubbish, gravel, or sand, or with all of these, to such an extent as to render it readily pervious to water.

It is more especially necessary to do this in those parts of the garden which are most in shade; particularly on the north side of the house, when it fronts the south. The ground being trenched, and the walks hollowed out, the whole should remain some weeks, and, if convenient, one whole winter, to settle, before the final smoothing of the surface, the gravelling or paving of the walks, the edging of them, and the planting of the trees and shrubs. When so much time cannot be allowed for the ground to settle, it is better not to trench it under where the walks and their edgings are to be placed, but merely to dig it; because, when trenched ground does not settle evenly, which it very seldom does, the materials of which the walk is formed, and its edgings, require, after a few months, to be taken up and relaid.