Thermae would be heated by a log fire before being channelled into the hot bathing rooms. The design of baths is discussed by Vitruvius in "De Architectura". "Thermae, balneae, balineae, balneum" and "balineum" may all be translated as "bath" or "baths", though Latin sources distinguish among these terms. "Balneum" or "balineum", derived from the Greek signifies, in its primary sense, a bath or bathing-vessel, such as most persons of any consequence among the Romans possessed in their own houses, and hence the chamber which contained the bath, which is also the proper translation of the word "balnearium". The diminutive "balneolum" is
Thermae A public bath was built around three principal rooms: the "caldarium" (hot bath), the "tepidarium" (warm bath) and the "frigidarium" (cold bath). Some "thermae" also featured steam baths: the "sudatorium", a moist steam bath, and the "laconicum", a dry hot room much like a modern sauna. By way of illustration, this article will describe the layout of Pompeii's Old Baths adjoining the forum, which are among some of the best-preserved Roman baths. The references are to the floor plan pictured to the right. The whole building comprises a double set of baths, one for men and the other for women.