Most of the preceding remarks apply equally to stone; but in reference to that material, there is one point to specially enforce,--namely, the advisability of not covering the whole of the surface with paint. There is about all stone a peculiar granulation, and in many varieties a slight silicious sparkle, which it is always well to preserve as far as possible. Illuminate, by all means, inscriptions, panels, friezes, &c., colour occasionally the hollows of mouldings, and gild salient members sufficiently to carry the colour about the monument, whether it may be a font, a pulpit, a tomb, a reredos, a staircase, a screen, or a doorway, and prevent the highly-illuminated portion from looking spotty and unsupported; but by no means apply paint all over. It is not necessary to produce a good effect; it destroys the surface and appearance of the stone, making it of no more worth than if it were plaster, and it clogs up all the fine arrises and angles of the moulded work or carving. Wherever stained glass is inserted in stonework, the application of illumination, or at any rate of coloured diaper-work of an analogous nature, is almost an imperative necessity, in order to balance the appearance of chill and poverty given to the stonework by its contrast with the brilliant translucent tints of the painted glass. In illuminating stonework, it seldom answers to attempt to apply decoration executed on paper or canvass; it should in all cases (excepting when it is at a great distance from the eye) be done upon the stone itself. The only exception is the one to which I shall allude in speaking of metal. Slate, although from its portability and non-liability to change its shape under variations of temperature, a convenient material for filling panels, and forming slabs for attachment to walls, is not to be recommended to the amateur, owing to the difficulty he will experience in effecting a good and safe adhesion between his pigments and the surface of the slate. In what is called enamelled slate, an excellent attachment is secured by gradually and repeatedly raising the slate to a high temperature; but the process would be far too troublesome and expensive for practice by the great majority of amateurs.