Manufacture of nails, 188--Locks and keys, 188--Stoves and grates, 190--Bells, 190--Brass handles, ornaments, &c., 191--Preservation of timber, 191--Various methods, 193--Kyanizing, 194--Soluble glass, 194--Its uses in preserving timber, &c., 197--Veneering, 198--Brunel’s method of cutting veneers, 198--Russian method, 199--The process of veneering, 199--Manufacture of glue, 201--The house decorator of Italy, 201--Fresco painting as applied to the decoration of houses, 206--Nature and difficulties of the art, 207--Notices of the ancient custom of decorating walls, 208--The practice of fresco painting, 208--The Cartoon, 209--The preparation of the wall, 210--The process of painting, 210--The colours and implements, 211--A fresco painter at work described, 212--General remarks on fresco painting, 214. CONCLUSION 215 The Useful Arts Employed in the Construction of Dwelling-Houses. CHAPTER I. THE WALLS. STONE AND STONE-WORK. The material mainly employed in the construction of buildings depends partly on the purpose for which the buildings are intended, and still more, perhaps, on the prevailing geological character of the surrounding country. In such a place as London, where there is an immense mass of tenacious clay beneath the vegetable soil, and where solid stone is not to be had, except by bringing it, at a great expense, from a distance of many miles, clay seems to be the natural material for dwellings; and thus we find that almost all the London houses are built of brick formed of clay. In other parts of Great Britain, such as Glasgow or Edinburgh, the case is very different; for, in those places, clay is scarce, and stone is plentiful. There are quarries not far from Edinburgh, and others within the very precincts of Glasgow, where an abundant supply of good building-stone is obtained at a very low rate. Hence it follows as a natural consequence, that the houses in those two cities exhibit a large proportion of stone structures; so much so, indeed, that an inhabitant of London, who is accustomed to see stone appropriated only to large important public buildings, is apt to imagine that the houses in the two northern cities must necessarily be very costly. This is by no means certain, however, for the builders in each city make use of those materials which may be most available. Whether stone form the main portion of the walls of a house, as in the cases just named, or whether it is only used in smaller degree, as in London houses, the operations by which it is worked and fitted are pretty much the same; and we will therefore devote this chapter to a brief description of the principal kinds of building-stone, followed by an outline of the _Mason’s_ operations. Principal Varieties of Building-stone.