Any shaped room may be adopted as a combined frigidarium and apodyterium so long as it fulfils the essential points--i.e. that it be spacious, capable of easy and perfect ventilation, and of being kept cool, light, and cheerful. In the cooling room the bather will often stay longer than in any other apartment, and no pains should be spared to render it healthy, comfortable, and attractive. The hygienic points to be attended to are, that there be an abundant supply of fresh cool air and an effective withdrawal of vitiated air; for the _cold-air bath_ in the cooling room is, in its way, as all-important as the bath of hot air. The freshness of the air is of equally vital importance, as much of the _invigorating_ effect of the bath--that effect which to the minds of the uninformed is _weakening_--results from submitting the heated skin to volumes of cold air.[2] In arranging any screens or screen walls in the cooling room, therefore, regard must be had to the method of ventilation, that there be no stagnant corners and recesses. The scheme of ventilation must be decided by the nature of the apartment and its position. In most cases the air is best admitted through the windows, fitted with fanlights falling backwards from the top, and extracted by a powerful self-acting exhaust at the ceiling level. In some positions extraction flues will have to be built, and, in others, flues of large area must conduct to the source from which the fresh air is drawn. Under certain circumstances perfect ventilation will not be obtainable without the aid of a powerful blowing fan-wheel driven by a motor of some sort, and running so as to exhaust the vitiated air. The means does not so much matter so long as the end be gained, and an ample supply of cool air obtained. A warm, close "cooling room" is worse than useless. In such places the bather will break out into renewed perspiration, and lie perspiring for hours, and become greatly weakened thereby, with a good chance of taking a chill on leaving the establishment. Cooling rooms will always remain sufficiently _warm_ in all weathers if they be in any ordinary relation to the heated apartments; but in the height of summer care is required to keep them sufficiently cool. Where simple, everyday precautions will not suffice, the air itself must be cooled, either by passing it through a cold chamber or over ice-boxes in inlet tubes, or through a water-spray. Only in exceptional cases, however, is it necessary to resort to such measures, as, contrary to the teachings of theorists, it has been found in practice that the proper temperature for the cooling room of a hot-air bath varies in different states of the weather, and should not remain constant all the year round. FOOTNOTES: [Footnote 2: Not _draughts_. The ancient Romans, it is curious to note, would walk in the open air after the bath; and both the _Frigidarium_ of the Romans and the _Mustaby_ of the Turks were, and are, open to the heavens.] CHAPTER V.