At the extremity of the hall, on either side to the right and left, if the house is large, there are two small recesses, rather than chambers, generally devoted to the ladies of the mansion; and in the centre of the tessellated pavement of the hall is invariably a square, shallow reservoir for rain water (classically termed impluvium), which was admitted by an aperture in the roof above; the said aperture being covered at will by an awning.

Near this impluvium, which had a peculiar sanctity in the eyes of the ancients, were sometimes (but at Pompeii more rarely than at Rome) placed images of the household gods--the hospitable hearth, often mentioned by the Roman poets, and consecrated to the Lares, was at Pompeii almost invariably formed by a movable brazier; while in some corner, often the most ostentatious place, was deposited a huge wooden chest, ornamented and strengthened by bands of bronze or iron, and secured by strong hooks upon a stone pedestal so firmly as to defy the attempts of any robber to detach it from its position.

It is supposed that this chest was the money-box, or coffer, of the master of the house; though as no money has been found in any of the chests discovered at Pompeii, it is probable that it was sometimes rather designed for ornament than use.
In this hall (or atrium, to speak classically) the clients and visitors of inferior rank were usually received.

In the houses of the more 'respectable', an atriensis, or slave peculiarly devoted to the service of the hall, was invariably retained, and his rank among his fellow-slaves was high and important.

The reservoir in the centre must have been rather a dangerous ornament, but the centre of the hall was like the grass-plot of a college, and interdicted to the passers to and fro, who found ample space in the margin.