, after the Romans began to imitate
their cavaedium. The word atrium is derived from the Atriates, a
people of Tuscany, from whom the pattern of it was taken." Originally,
then, the atrium was the common room of resort for the whole family,
the place of their domestic occupations; and such it probably
continued in the humbler ranks of life. A general description of it
may easily be given. It was a large apartment, roofed over, but with
an opening in the centre, called _compluvium_, towards which the roof
sloped, so as to throw the rain-water into a cistern in the floor
called _impluvium_.

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