To the latter may be attributed the chief architectural works of the country; the ancient Etruscan walled cities resembling, in their general construction, those of Tiryns and Mycenæ. Judging from the remains found upon the soil at the present day, the Etruscans used their knowledge of the laws of building principally in the erection of tombs. Of temples there now remain no traces; but, according to Vitruvius, they were composed, as a rule, of the rectangular chamber, or cella, of the Greeks, which was divided into three parts, and preceded by a porch of Tuscan columns. The origin of the latter he describes as follows: “The Greek colonists, having brought to Etruria, the Tuscany of to-day, their acquaintance with the proportions of the Doric order, which was the only one as yet used in Greece, they employed this order there during a long period, in the same manner as in the country where it originated; but finally they changed it in several respects; they lengthened the column, and added a base to it; they altered the capital, simplified the entablature, and, thus changed, it was adopted by the Romans, under the name of the Tuscan order.” Etruscan tombs varied with the nature of the districts in which they were erected. In the flat portions of the country they consisted usually of an earthen cone raised upon a circular foundation of masonry, with one or more chambers within for the reception of the dead. The largest of these tumuli was that called the Cucumella, at Vulci. In the mountains, where material was abundant, it was customary to bury the dead in a square stone chamber, surmounted by a pyramidal roof, and entered by a doorway ornamented with the Greek architrave. There are several examples of these at Castel d’Asso. A third form of sepulchre was the hypogee, or underground tomb, the entrance to which was marked by a colonnade of the Tuscan order, carved in the face of the rock; the interior apartment being usually rectangular, and reached by a staircase. The walls were decorated with paintings, and the tomb filled with vases, tripods, arms, and other votive offerings. The body was generally either placed in a stone sarcophagus or laid upon a bronze bed. The ceilings in the older tombs were either flat, being cut in the natural rock, with piers left as supports, and ornamented with sunken panels, or constructed of inclined slabs, resting against and sustaining each other. The corbelled vaults, similar to those of Mycenæ, were employed for a considerable number of these buildings, but were subsequently relinquished for vaults of voussoirs, or wedge-shaped stones. The invention of the semicircular vault, the joints of which converge to a common centre, was long attributed to the Etruscans, but we have seen that recent discoveries have shown that it was already in use in Egypt and Assyria many centuries before. This principle, however, was the chief feature of Etruscan architecture, and its great legacy to succeeding styles.