PAVING, the construction of ground-floors, streets, or highways, in such a manner that they may be conveniently walked upon. In Great Britain the pavement of the streets and roads usually consists of flint or rubble-stone; but courts, stables, kitchens, halls, churches, and the like, are paved with tiles, bricks, flags, or fire-stone, and sometimes with a kind of freestone or ragstone.
Pavements of churches frequently consist of stones of several colours, but chiefly black and white, and of several forms, but chiefly squares and lozenges, artfully disposed. Indeed there needs no great variety of colours to produce a surprising diversity of figures and arrangements. M. Truchet, in the Memoirs of the French Academy, has shown by the rules of combination, that two square stones, divided diagonally into two colours, may be joined together chequerwise in sixty-four different ways; which appears surprising enough, since two letters or figures can only be combined two ways. The reason is, that letters only change their situation with regard to the first and second, the top and bottom remaining the same; but in the arrangement of these stones, each admits of four several situations, in every one of which the other square may be changed sixteen times, which gives sixty-four combinations.
Indeed, from a further examination of these sixty-four combinations, he found that there were only thirty-two different figures, each figure being repeated twice in the same situation, though in a different combination, so that the two differed from each other only in the transposition of the dark and the light parts.