The roof around the compluvium was edged with a row of highly ornamented tiles, called antefixes, on which a mask or some other figure was moulded. At the corners there were usually spouts, in the form of lions' or dogs' heads, or any fantastical device which the architect might fancy, which carried the rain-water clear out into the impluvium, whence it passed into cisterns; from which again it was drawn for household purposes. For drinking, river-water, and still more, well-water, was preferred. Often the atrium was adorned with fountains, supplied through leaden or earthenware pipes, from aqueducts or other raised heads of water; for the Romans knew the property of fluids, which causes them to stand at the same height in communicating vessels. This is distinctly recognized by Pliny,[5] though their common use of aqueducts, in preference to pipes, has led to a supposition that this great hydrostatical principle was unknown to them. The breadth of the impluvium, according to Vitruvius, was not less than a quarter, nor greater than a third, of the whole breadth of the atrium; its length was regulated by the same standard. The opening above it was often shaded by a colored veil, which diffused a softened light, and moderated the intense heat of an Italian sun.[6] The splendid columns of the house of Scaurus, at Rome, were placed, as we learn from Pliny,[7] in the atrium of his house. The walls were painted with landscapes or arabesques--a practice introduced about the time of Augustus--or lined with slabs of foreign and costly marbles, of which the Romans were passionately fond. The pavement was composed of the same precious material, or of still more valuable mosaics. [Illustration: VESTIBULE OF A POMPEIAN HOUSE.] The tablinum was an appendage of the atrium, and usually entirely open to it. It contained, as its name imports,[8] the family archives, the statues, pictures, genealogical tables, and other relics of a long line of ancestors. Alæ, wings, were similar but smaller apartments, or rather recesses, on each side of the further part of the atrium. Fauces, jaws, were passages, more especially those which passed to the interior of the house from the atrium. In houses of small extent, strangers were lodged in chambers which surrounded and opened into the atrium. The great, whose connections spread into the provinces, and who were visited by numbers who, on coming to Rome, expected to profit by their hospitality, had usually a _hospitium_, or place of reception for strangers, either separate, or among the dependencies of their palaces.