When the shape is naturally either concave, or perfectly flat, the house would not be habitable, unless the ground sloped sufficiently to throw the water from it: this is often effected, in a slight degree, merely by the earth that is dug from the cellars and foundations: but if, instead of sinking the cellars, they were to be built upon the level of the ground, they may afterwards be so covered with earth, as to give all the appearance of a natural knoll, the ground falling from the house to any distance where it may best unite with the natural shape, as shewn at E, F, and G: or, as it frequently happens that there may be small hillocks, H and I, near the house, one of them may be removed to effect this purpose*. This expedient can also be used in an inclined plane, falling towards the house, where the inclination is not very great, as shewn at L; but it may be observed of the inclined plane, that the size of the house must be governed in some measure by the fall of the ground; since it is evident, that although a house of a hundred feet deep might stand at K, yet it would require an artificial terrace on that side; because neither of the dotted lines shewn there would connect with the natural shape; and where the ground cannot be made to look natural, it is better, at all times, to avow the interference of art, than to attempt an ineffectual concealment of it. Such situations are peculiarly applicable to the Gothic style, in which horizontal lines are unnecessary.
These sections can only describe the shape of the ground as it cuts across in any one direction: but another shape is also to be considered: thus it generally happens that a knoll is longer one way than the other, or it may even extend to a natural ridge, of sufficient length for a long and narrow house; but such a house must be fitted to the ground, for it would be absurd in the architect to place it either diagonally or directly across such a ridge: the same holds good of the inclined plane, which is, in fact, always the side of a valley, whose general inclination must be consulted in the position of the building. A square house would appear awry, unless its fronts were made to correspond with the shape of the adjacent ground.
I shall conclude this digression by observing, that, on a dead flat or plain, the principal apartments ought to be elevated, as the only means of shewing the landscape to advantage. Where there is no inequality, it will be very difficult to unite any artificial ground with the natural shape: it will, in this case, be advisable either to raise it only a very few feet, or to set the house on a basement story. But whereever a park abounds in natural inequalities, even though the ground near the house should be flat, we may boldly venture to create an artificial knoll, as it has been executed at Welbeck.
*[As at Donington, a seat of Earl Moira, where the house forms a quadrangle, inclosing an inner court, a whole story lower than appears externally.].