At Fig. 5 are shown different ways of arranging couches in the frigidarium. A shows the objectionable arrangement spoken of; B is the comfortable, s.p.a.cious divan; C the method of placing couches in pairs; and D is a private couch suitable for ladies" baths.
The floor of a cooling room must be boarded. In a bath where cost is subordinate to excellence, a parquetry floor may be provided, and mats employed, as cleaner than fixed carpets. The walls and ceilings may be treated in any manner that may be chosen--plastered, papered, or decorated with colour.
[Ill.u.s.tration: FIG. 5.
Methods of arranging Couches in Cooling Room.]
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 s.p.a.cious, 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 circ.u.mstances 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 pa.s.sing 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.
HEATING AND VENTILATION.
Of the many questions that merit attention and study in connection with the Turkish bath, all sink into insignificance by the side of that of the _heating_ and the _nature of the heat_ supplied in the sudatory chambers. Other things being equal, it is, after all, the _heating_ that distinguishes one bath from another on the score of excellence. The heating of the "bath" is the Alpha and Omega of the whole matter.
There are two ways in which heat may be applied to the body--by direct radiation, as from the sun or an open fire; and by convection, as through a volume of air.
The ancient Roman bathers, with floors below them which rested upon _pilae_, or little pillars of brick or tile, around which the flames and hot gases from the furnace played, and surrounded by heated, hollow walls, evidently submitted themselves to the action of a heat that must have been of a purely radiating character.
So, also, in a less perfect manner, the Turks, who employ flues running beneath the floors, and the Moors, who adopt stoves visible to the bathers.
Theoretically, radiant heat in a bath is vastly superior to that which is transmitted to the body through the medium of the air. Its virtues have been extolled by David Urquhart and other eminent authorities on the bath. "There is a difference," says Mr. Urquhart, "between radiating and transmitted caloric.... I cannot pretend to treat of this great secret of nature; to work out this problem a Liebig is required. This I can say, that such heat is more endurable than common heat. There is a liveliness about it which transmitted heat lacks. You are conscious of an electrical action. It is to transmitted heat what champagne is to flat beer.... Let us drop, if you please, the word "bath": it is "heat."
Let us away with that absurdity "hot-air": it is the application of heat to the human frame." Elsewhere this writer has pointed out that the terms _thermae_, _sejac_, and _hammam_--the names given to the bath by the Romans, Moors, and Orientals proper--mean _heat_, and not "hot-air"
or "hot-air bath."
My own studies, observations, and experience lead me to the conclusion that the direction in which we shall improve the "Turkish bath" will be in the way of providing sudatories that shall give off pure, radiant heat in such a manner that the whole surface of the body may be sensible of a degree of heat, while the lungs may breathe comparatively cool air--air that has not pa.s.sed over the sides of a fiery furnace and been suddenly raised to an enormous temperature, but which has received its heat by a gentle and gradual process of warming. Under this system the heat of which we are sensible is as the gentle Zephyr to rude Boreas or the biting eastern winds. If we go into a kiln of brickwork, such as is employed in firing clay goods, after the charge has been removed and all fumes and odours have disappeared, we shall note the soft and balmy nature of the heat that radiates directly from the walls and vaulting.
We are, to all practical intents and purposes, _in a Roman laconic.u.m_.
The thick walls have been highly charged with caloric during the firing of the bricks or other articles. They have absorbed vast quant.i.ties of heat, and are now giving off the same to the enclosed air and to ourselves standing within. In the old Roman bath the walls were charged with caloric by means of innumerable earthen tubes lining the sides of the laconic.u.m, and covered with a peculiar plaster. But in both cases the nature of the resultant heat is identical. It radiates to one from all sides. There is no acrid biting of the face such as one feels in the worst type of _hot-air_ baths; no unpleasant fulness or aching of the head; and no panting or palpitating. Such is the "bath" of pure radiant heat, a thing totally distinct from, and altogether of a different genus to, the bath of heated air. And one might be pardoned for the enthusiasm which would lead one to suggest that it is only in the supplying of this kind of radiant heat in the modern bath that true and rapid progress can be expected, and possibly that not until this great or partial--according as the system of radiation and convection pertains in existing baths--revolution has been effected, will the bath, at present used by the few, become the custom of the many. Some day, peradventure, this hypothetical method of employing pure radiant heat may be rendered possible and practicable, and we may be placed in a bath where we shall receive great heat whilst breathing a comparatively cool atmosphere, and thus receive a measure of that electrical invigoration we experience when, in some sheltered bathing cove, we have exposed our bodies to the fiercest rays of the morning sun whilst yet we breathe the fresh, cool, ozone-laden air.
Till modern invention, however, has provided us with this desideratum in the heating of the bath, we must be satisfied with existing methods. And unless something really practical is perfected, it is far wiser to rely upon the system of heating by convection through the air--the principle, generally adopted, of continuously pa.s.sing large quant.i.ties of freshly-heated air through the sudatory chambers; exposing, however, the heating apparatus, so that a maximum of radiant heat may be obtained; and carefully guarding against injuring the air whilst raising its temperature. If only existing baths were in perfect harmony with this principle, one would have little cause for complaint, and might the more leisurely await the perfecting of the true radiating principle of heating, which I am satisfied is the one upon which we must base all our hopes for the future of the "Turkish" bath.
For practical purposes, it will suffice if the method of heating and ventilating a bath on the hot-air principle be explained. This I shall now do, and subsequently give plans and instructions for methods of heating and ventilating on systems where, by the exposure of the heating surfaces of furnaces, a large proportion of radiant heat is thrown into the hot-rooms.
The necessary appliances, and arrangements for the heating and ventilation of a bath on the ordinary hot-air principle comprise a furnace in its chamber, with flues or shafts supplying cold, and drawing off the heated air, and a stokery with provisions for firing and storing c.o.ke, &c. Too often the stokery is unscrupulously cramped, and the life of the stoker thereby rendered anything but pleasant. Its design is a simple matter, and perhaps for this reason neglected. The arrangement and construction of the furnace chamber requires care, and the selection of a stove or furnace great judgment. As regards the latter feature, the most important point to consider is the nature of the heating or radiating surfaces. What will raise the air to the required temperature, without in the process depriving it in any way of its vitalising elements, and without adulterating it with either smoke and fumes from leakage, or with particles of foreign matter given off from the material employed in its construction?
There is nothing really better as a radiating surface than ordinary firebrick. From this material a soft heat is given off, differing in quality from that obtained from iron. An iron furnace, however, requires less thought in design, gives less trouble in fitting up, and is cheap, economical, and expeditious. Stoves, therefore, with an iron radiating surface, have been largely adopted in the past, in spite of the objection that, when super-heated, particles of metal are thrown into the air of the hot rooms. Of iron furnaces there are many placed before the public; but though all are doubtless suited to ordinary requirements, there are few that are capable of creditably fulfilling the conditions indispensable for the hygienic heating of the air of a Turkish bath.
These conditions may be summarised as follows:--
1. A maximum of heating-surface, with a minimum of grate s.p.a.ce.
2. Perfect immunity from the danger of leakage from the furnace into the hot-air chamber or conduit.
3. Freedom from the defect of liability to overheat the air.
4. Inability to adulterate the air by throwing off matter from the heating surfaces.
Such primary essentials must be constantly borne in mind by the designer of furnaces for the Turkish bath. Their importance must be obvious to all.
Of the many iron stoves, Messrs. Constantine"s "Convoluted" stove has been adopted the most frequently, as an eminently practical furnace for the effective heating of the sudatory chambers. The appearance of this stove is familiar to all architects, and it will be unnecessary, in these pages, to minutely describe its construction.
[Ill.u.s.tration: FIG. 6.
View of a small Furnace Chamber, with portion of wall broken away to show the "Convoluted" Stove.]
The method of constructing a furnace suitable for a small public bath is, however, shown at Fig. 6. The excavations for stokery and heating chamber being completed, and the position of the furnace determined a solid foundation of concrete must be prepared, upon which the brickwork to support the stove must be laid. At the same time, the foundations for walls of furnace chamber, stokery, c.o.ke store, and the side walls for the horizontal cold-air conducting flues will be prepared. These latter must then be built in half-brick with glazed interior face, and the furnace inclosed in similar work, as shown in perspective sketch. The flues must be covered with York stone slabs 3 in. thick, up to within three inches or so of the convolutions of the stove, at which distance the side walls of the furnace must be erected, the back one similarly, and the front one round the four projecting doors, which are, respectively, the ash-pit door, the fire door, and two doors for cleansing the horizontal smoke-box and interior of convolutions. The furnace walls must be continued up to a few inches above the bend of iron smoke flue, and then--if, as shown, the furnace be small--covered with a 4-in. York slab in one piece. If the furnace be large, a flat brick arch must form the covering, as at Fig. 8, where this arch supports the flooring of the laconic.u.m. The openings for the admission of the heated air into the conduit leading into the hot rooms may be either directly above, as shown in the last-named ill.u.s.tration, or in the side, as in Fig. 6, with inclined flues. As a rule, it is more economical, in heating on the principle now under consideration, to place the furnace below the level of the hot rooms; but if desirable to place both on one level, the back wall of the furnace chamber becomes the party wall of the laconic.u.m, and it must be stopped short of the ceiling, and the air debouched over it.
In cheap baths the interior face of furnace chamber may be of stock brickwork; but best glazed work should be adopted in good ones. All hot and cold-air ducts should be similarly lined with glazed ware. In first-cla.s.s work the floors of horizontal and inclined flues should be of white glazed tiles set in cement. Manholes must be provided for cleaning when necessary. Every portion of furnace chamber, flues, shafts, and conduits for hot and cold air must be "get-at-able" either by means of manholes or by long brushes. Air-tight doors must be indicated on the plans wherever this necessity demands them.
The iron smoke-pipe from furnace must be conducted to the smoke flue, and the connection between furnace chamber and flue hermetically sealed.
The walls for a small furnace chamber need not be more than 4-1/2 in.
thick. Large furnaces require walls one-brick thick.
[Ill.u.s.tration: FIG. 7.
An Air Filter.]
The cold-air flues leading from either side of the furnace must be conducted to their respective inlets. If possible, at least two inlets should be provided, facing different ways: this with regard to the possibility of certain winds drawing the air out where it is wanted to enter. The openings should be vertical, like windows, and, in cities, furnished with a solid frame and cas.e.m.e.nt, fitted with louvres of plate gla.s.s with polished edges. Between the rebate and the cas.e.m.e.nt it is a good plan to leave a s.p.a.ce of an inch and a half for a movable stretcher-frame holding several layers of "cheese-cloth" to filter the air. The construction of such an air filter is shown at Fig. 7. The gla.s.s louvres keep out the wet, and throw off coa.r.s.e particles of falling soot; and the provision of a movable stretcher permits the cloths to be frequently changed for clean ones--a very important point, though little heeded, if not, perhaps, wholly ignored.
[Ill.u.s.tration: FIG. 8.
Plans and Section of a Furnace Chamber, &c., for a Bath on the ordinary Hot-air Principle.]
The position of air intake is a matter of great importance, especially in large towns. It evidently is bad to draw a supply of air from the bottom of an area. Even the position shown in Fig. 8 is not good: the shaft should be carried higher. The best places for the intakes are where there is always a current of pure air blowing, and away from smoky chimneys. Theoretically, it would seem that the higher the level of intake the better; but in cities, by going high we get among the belching chimney-tops, even if we escape the stagnation below. Moreover, a high inlet with a strong wind tending to exhaust the air in the shaft might find the architect with the cold air sweeping through his bath, and all the heated air rushing up the supply-shaft. A large "lobster-back" automatically turning _towards_ the wind, would in many cases prevent such a disastrous result. Even in low-level intakes, as I have said, trouble will sometimes arise from the same cause. This may be remedied by providing more than one inlet, so that only the one facing the current of air will be employed, the other being closed, which could be effected by fixing the gla.s.s louvres, spoken of above, on pivots, and connecting them with a rod and adjustable rack. It would be a very simple matter to make the wind itself automatically open and shut the louvres.
The theory of the heating and ventilation of the hot rooms requires most careful study, and the particular scheme to be adopted in any new bath must be well considered with respect to the restrictions of the site. At Fig. 8, I have endeavoured to show how to make the best of what is perhaps a bad job: the site only admits of ventilation at a back area, it is impossible to construct flues anywhere else, and the fresh air must be drawn from the same area. On the ground floor are cooling and dressing rooms; the bath rooms are in the bas.e.m.e.nt and the furnace in a sub-bas.e.m.e.nt, reached from a pa.s.sage at the end of the stairs for the bather. Two convoluted stoves are shown in a vault; three air-inlets are provided, and the foul air is drawn up into the smoke flues, two in number, which, above, could join one another. Let us follow the air in its pa.s.sage through the bath. Entering at the intakes, any coa.r.s.e impurities are thrown off by the smooth louvres, and the tendency of finer particles to rush in is checked by the stretched canvas cheese-cloths. Thus deprived of its actually visible impurities, the air pa.s.ses through a longer or shorter conduit of glazed brickwork until it reaches the horizontal flues running to beneath the furnace walls, along which it is rapidly drawn, and, ascending between the walls and heating surfaces and between the two adjacent heating surfaces, absorbs the radiating heat and enters the laconic.u.m by way of the rectangular shaft constructed above the vault spanning the two stoves.
Questions of temperature I will omit for the present. The air, on pa.s.sing through the laconic.u.m, will be practically pure, as it is in such great bulk compared with the number of occupants of this highly-heated chamber, and it will not be absolutely necessary to provide ventilators. These should commence in the calidarium, and should, in the scheme of ventilation here considered, be so disposed that the nearer they are to the lavatorium and shampooing-room, the more frequent will they become. The object of this disposition of outlets for vitiated air is, that the cross currents thus created may not interfere with the main flow from the heating chamber to the lavatorium. Were too many ventilators to be placed near the hotter end of the sudatorium, this stream would be diverted. Too much of the freshly-heated air would flow out at these points, and the onward movement of the air would be enfeebled. There would then be difficulty in maintaining the temperature in the tepidarium and lavatorium.
In pa.s.sing onward through the various rooms, two changes are wrought in the air: it loses so much of the caloric with which it is charged for every foot it travels, and it becomes laden with the exhalations from the lungs of the bathers. A large proportion of carbonic acid is thrown into the air, and as the normal temperature of the human body remains, in a healthy person, at about 98 Fahr., and rises but a few points even when submitted to the action of heat, these exhalations, in addition to being heavier than air, are very much below the average temperature of a sudatory chamber. Consequently they fall, and must be extracted at the floor level.
The total area of the outlets for vitiated air should be about equal to the area of the narrowest part of the shaft that conducts the fresh, hot air from the heating chamber. Thus, supposing the latter to be 5 superficial feet, and the size of outlet ventilators a clear 12 in. by 3 in., there may be 20 ventilators disposed round the bath-rooms, say 4 in the calidarium, 7 in the tepidarium, and 9 in the combined shampooing room and lavatorium.
In the diagrams at Figs. 8 and 9 the foul-air conduit is the s.p.a.ce comprised under the marble-topped benches running round the hot rooms.
At the end of the laconic.u.m they enter flues, which I have shown as running side by side with the smoke flues.
Other methods of heating the air, besides those mentioned, include coils of iron flue-pipes in a brick chamber--a principle that has been frequently adopted in the past--and plain cylindrical iron radiating stoves, such as employed at the Hammam in Jermyn Street.