It came to be gradually recognized that the form of the pier should be subservient to, and made to correspond with, the arches and the column receiving the arch rib of the vault above, which it had to sustain. This was effected at first by a square pier, with rectangular projections on each side, forming abutments for the reception of the constructional arrangement above. Subsequently these were replaced by pilasters and engaged columns on each face, three of which supported the rear and side arches of the nave, the fourth being continued up to the springing of the vault, and redeemed from exaggerated effect by bands or string-courses. There are good examples in France at Vezelay, Beaune and Langres and Autun. In England the contemporary architects usually employed square or circular masses of solid masonry, carrying a heavy abacus, these pillars being sometimes ornamented with a fluting, as in the crypt at Canterbury, or with zigzag patterns, as at Waltham Abbey, Durham, and Lindisfarne. The capitals of Romanesque columns are especially interesting, for they became constructively useful instead of simply ornamental, as were those used in the Roman orders. The section of the arch rib being square and the column round, it was necessary to afford support to the overlapping corners, the whole surface of the projecting tile or abacus being occupied by the upper masonry, instead of the line of the shaft being continued up, as had been done in Rome. The capital was therefore made to spread outward from the shaft in order to corbel the superstructure. [Illustration: COMPARATIVE SERIES, SHOWING GREEK, ROMAN, ROMANESQUE, AND GOTHIC METHODS OF SUPPORT. 1. Greek Lintel. 2. Roman Arch, showing False Lintel. 3. Vault Springing from Entablature. 4. Arch Springing 5. Romanesque Column, with Arches Springing from Outer Edge of the Capital. 6. Romanesque Pier. 7. Gothic Pier.] A simple form of this is found in many German, Italian, and English examples, the upper part of the capital being a cube and the lower a hemisphere. The early examples generally imitate those of the Corinthian order in a rude fashion corresponding with the poverty of talent of the period. The capitals of the twelfth century are better carved and better suited to the services they have to perform. Figures representing biblical subjects are introduced in some and in others strange animals and conventional foliage, sometimes arranged as the acanthus leaf had been in the Roman models. The proportions of the Classic column were also departed from, the capital often being a quarter or a sixth of the whole column; its height being regulated by the size of the beds of stone, which were generally low. In Germany, however, the older proportions were more closely adhered to. The quality of the stone determined in a great measure the depth of the carving, the harder kinds having less depth of incision and the style of ornament applied to them resembling the Byzantine.