It would be easy to multiply examples to show to what perfection the science of proportion was carried by the experimental processes above described during the existence of the true styles of architecture, and how satisfactory the result is, even upon those who are not aware of the cause; and, on the other hand, how miserable are the failures that result either from the ignorance or neglect of its rules. Enough, it is hoped, has been said to show that not only are the apparent proportions of a building very much under the control of an architect independent of its lineal dimensions, but also that he has it in his power so to proportion every part as to give value to all those around it, thus producing that harmony which in architecture, as well as in music or in painting, is the very essence of a true or satisfactory utterance. XI.—CARVED ORNAMENT. Architectural ornament is of two kinds, _constructive_ and _decorative_. By the former is meant all those contrivances, such as capitals, brackets, vaulting shafts, and the like, which serve to explain or give expression to the construction; by the latter, such as mouldings, frets, foliage, &c., which give grace and life either to the actual constructive forms, or to the constructive decoration. In mere building or engineering, the construction being all in all, it is left to tell its own tale in its own prosaic nakedness; but in true architecture construction is always subordinate, and as architectural buildings ought always to possess an excess of strength it need not show itself unless desired; but even in an artistic point of view it always is expedient to express it. The vault, for instance, of a Gothic cathedral might just as easily spring from a bracket or a corbel as from a shaft, and in early experiments this was often tried; but the effect was unsatisfactory, and a vaulting shaft was carried down first to the capital of the pillar, and afterwards to the floor: by this means the eye was satisfied, the thin reed-like shafts being sufficient to explain that the vault rested on the solid ground, and an apparent propriety and stability were given to the whole. These shafts not being necessary constructively, the artist could make them of any form or size he thought most proper, and consequently, instead of one he generally used three small shafts tied together at various intervals. Afterwards merely a group of graceful mouldings was employed, which satisfied not only the exigencies of ornamental construction, but became a real and essential decorative feature of the building.