The Corinthian architrave in Hellenic usage consisted, it will be remembered, of three bands, as in the Ionic order. The Romans frequently embellished the middle one with a version of the anthemion motive. They also added enrichments to the bed mould beneath the frieze. The latter was frequently carved with acanthus scrolls, grotesque figures, and ox-skulls, and garlands. The cornice was also enriched with carved ornament, of which the most characteristic were _modillions_ or brackets, which appear to support the cornice. The Composite order was an invention of the Romans and possibly suggested by the capitals of the =Erechtheion= in =Athens=, where the Ionic spirals appear above a necking carved with anthemion ornament. The capital of the Composite order consisted in the upper part of Ionic spirals, often richly decorated with foliage, and in the lower of two rows of acanthus leaves, as in the Corinthian order, which was followed also in the other details of the column and entablature. The mouldings in Hellenic architecture are distinguished by the refinement of the contours, in Roman by the richness of carved ornament. The anta, which appears in Greek temples at the corners of the cella walls was developed by the Romans into the _pilaster_. This was a square pier, projecting about one-sixth of its width from the wall; used either to divide up and decorate the wall surfaces, or to serve as a “respond” to a column. It was frequently fluted and corresponded with the column in its details. =Arch-Vaulting.=--The Romans did not invent the arch, but generalised its use and elaborated it into vaulting, thus introducing into architecture an element of construction capable of endless application and lending itself not only to utility but also to variety and magnificence. In doing so they were assisted by their discovery of the use of concrete. By means of supports and sheathings of rough timber, temporarily erected, they were able to cast their arches or vaultings in any form and practically of any size. The concrete “set” quickly and the arch or vaulting thus became a solid mass, which exerted but little thrust and covered the space with the rigidity of a lid or cup.