With regard to clays in general, and the art of working in them, it may be remarked that archæologists have told us little. They have divided the past history of the race into the stone, bronze, and iron periods, but have told us nothing of the age of clay, or of an art which we venture to say was one of the oldest invented by man. Clay and clay-workers are found everywhere; and the material is one of the most abundant provided by Nature. The first man would find it soft, yielding, and ready to his hands, with the impressions of birds and beasts, suggestive of the use to which it might be put, and the act of moulding it into form would be as natural as that of plucking fruit from a tree, or that of taking up a stone to strike a harder blow than the hand could give. Hardening it in the sun or baking it in a wood fire would be equally simple; whilst the act of fashioning a shapeless mass into an enduring form would yield so much pleasure that it would be repeated. That the art is pre-historic, and began before the race commenced a record of its doings, is evident from specimens which accompany the remains of men of whose tribe and nation we know nothing. Living beings stronger than man had been masters of the globe before he came, and ignobly perished, leaving but the impressions of their bones to tell of their existence; but man brought with him a new element by which to subjugate and subdue the materials he saw around him to his use, and left behind him more enduring monuments. Other enduring materials pressed into the service of architects of ancient and modern times were once as incoherent a mass of atoms, and as unshapable as these clays, and were either earths, clays, or sands, which Nature by the processes of kneading, pressing, and baking, in her great laboratory, converted into stone. We find them to some extent ready shaped to hand in the quarry, and we cut them into cubes or blocks, and pile them up in buildings, according to the humour or taste of the time. Bricks are artificial stones, and in making them we follow the example Nature set us only that we cut the plastic material first of all to the size we desire it, then convert it into stone by heat; and this artificial stone, we venture to say, for durability and beauty, is equal even to Nature’s own production, and quite as suggestive to the mind. Nature’s finished material may be deemed more suitable for churches; but artificial stone, fashioned into shape by man, is quite as appropriate for a dwelling in which the highest social sanctities gather. Indeed the art of using artificial stone appears to have been roused from the torpor into which it had fallen since Roman and Flemish authorities set such good examples. People had been so long accustomed to see brickwork used only for inferior houses, and stone for buildings of greater pretensions that, till recently, English bricks have scarcely had justice done them.