The two physicians, Galen and Celsus, differ in some respects as to the order in which the baths should be taken; the former recommending first the hot air of laconicum, next the bath of warm water, afterward the cold, and finally to be well rubbed; while the latter recommends his patients first to sweat for a short time in the tepid chamber without undressing, then to proceed into the thermal chamber, and after having gone through a regular course of perspiration there, not to descend into the warm bath, but to pour a quantity of warm water over the head, then tepid, and finally cold; afterward to be scraped with the strigil and finally rubbed dry and anointed. Such in all probability was the usual habit of the Romans when the bath was resorted to as a daily source of pleasure, and not for any particular medical treatment; the more so as it resembles in many respects the system of bathing still in practice among the Orientals who succeeded by conquest to the luxuries of the enervated Greeks and Romans. Having thus detailed from classical authorities the general habits of the Romans in connection with their systems of bathing, it now remains to examine and explain the internal arrangements of the structures which contained their baths, which will serve as a practical commentary upon all that has been said. Indeed, there are more ample and better materials for acquiring a thorough insight into Roman manners in this one particular than for any of the other usages connected with their daily habit. In order to make the subjoined description clear, a reproduction from an old woodcut of a fresco painting on the walls of the thermæ of Titus at Rome, is here reproduced, showing in broken perspective the general arrangement of one of the baths known as the thermæ. Heat was supplied to warm the apartments and the water used in the baths by the furnace shown extending under the entire floor of the establishment. This furnace was known as a Hypocustum. To the right may be seen the vessels in which water for the baths was heated. The topmost vessel, the Frigidarium, contained cold water from which the hot water tanks and the various baths were supplied. Next in order is the tepidarium, in which water of moderate temperature was stored, and in the lowest, the caldarium, was heated the hottest water used in the baths. After the end of the republic, large establishments used to have a separate steam bath, the laconicum, and in this apartment, or sometimes adjoining the tepidarium, was the Clipeus, a small circular chamber covered by a cupola. The Clipeus received its light through an aperture in the center of the dome, and this aperture served also as a vent from the chamber. The Clipeus was heated by means of a separate heating apparatus, and its temperature could be raised to an enormous degree or could be regulated to suit the bather by raising or lowering the shield. [Illustration: Thermæ of Titus at Rome] [Illustration: Clipeus. From an old woodcut]