Other specimens of these two types of column vary widely from those of Karnak, for Egyptian architects did not feel obliged, like Greek architects, to conform, with but slight liberty of deviation, to established canons of form and proportion. Nor are these two by any means the only forms of support used in the temple architecture of the New Empire. The "proto-Doric" column continued in favor under the New Empire, though apparently not later; we find it, for example, in some of the outlying buildings at Karnak. Then there was the column whose capital was adorned with four heads in relief of the goddess Hathor, not to speak of other varieties. Whatever the precise form of the support, it was always used to carry a horizontal beam. Although the Egyptians were familiar from very early times with the principle of the arch, and although examples of its use occur often enough under the New Empire, we do not find columns or piers used, as in Gothic architecture, to carry a vaulting. In fact, the genuine vault is absent from Egyptian temple architecture, although in the Temple of Abydos false or corbelled vaults (cf. page 49) do occur. Egyptian architects were not gifted with a fine feeling for structural propriety or unity. A few of their small temples are simple and coherent in plan and fairly tasteful in details. But it is significant that a temple could always be enlarged by the addition of parts not contemplated in the original design. The result in such a case was a vast, rambling edifice, whose merits consisted in the imposing character of individual parts, rather than in an organic and symmetrical relation of parts to whole.