SECTION XXXI. LAW II. _Science of inner structure is to be abandoned._ As the body of the structure is confessedly of inferior, and comparatively incoherent materials, it would be absurd to attempt in it any expression of the higher refinements of construction. It will be enough that by its mass we are assured of its sufficiency and strength; and there is the less reason for endeavoring to diminish the extent of its surface by delicacy of adjustment, because on the breadth of that surface we are to depend for the better display of the color, which is to be the chief source of our pleasure in the building. The main body of the work, therefore, will be composed of solid walls and massive piers; and whatever expression of finer structural science we may require, will be thrown either into subordinate portions of it, or entirely directed to the support of the external mail, where in arches or vaults it might otherwise appear dangerously independent of the material within. SECTION XXXII. LAW III. _All shafts are to be solid._ Wherever, by the smallness of the parts, we may be driven to abandon the incrusted structure at all, it must be abandoned altogether. The eye must never be left in the least doubt as to what is solid and what is coated. Whatever appears _probably_ solid, must be _assuredly_ so, and therefore it becomes an inviolable law that no shaft shall ever be incrusted. Not only does the whole virtue of a shaft depend on its consolidation, but the labor of cutting and adjusting an incrusted coat to it would be greater than the saving of material is worth. Therefore the shaft, of whatever size, is always to be solid; and because the incrusted character of the rest of the building renders it more difficult for the shafts to clear themselves from suspicion, they must not, in this incrusted style, be in any place jointed. No shaft must ever be used but of one block; and this the more, because the permission given to the builder to have his walls and piers as ponderous as he likes, renders it quite unnecessary for him to use shafts of any fixed size. In our Norman and Gothic, where definite support is required at a definite point, it becomes lawful to build up a tower of small stones in the shape of a shaft. But the Byzantine is allowed to have as much support as he wants from the walls in every direction, and he has no right to ask for further license in the structure of his shafts. Let him, by generosity in the substance of his pillars, repay us for the permission we have given him to be superficial in his walls. The builder in the chalk valleys of France and England may be blameless in kneading his clumsy pier out of broken flint and calcined lime; but the Venetian, who has access to the riches of Asia and the quarries of Egypt, must frame at least his shafts out of flawless stone.