Ill. Food
V. The dwelling
old men and invalids for whom a large amount of heat is necessary. For the sake of cleanliness the counterpane is supplied with a cover and the underbed with sheets from linen or calico, which can be easily washed or exchanged. By means of frequent and regular shaking and airing the bedding should be freed from the dust particles and skin excreta which accumulate in it. The frame of the bed in order to render the access of air easy, must be raised from the ground and is also to be kept carefully from vermin.
§ 110. Cleanliness of clothing and bedding. The clean-liness of clothing and bedding is of the very greatest impor-tance for the preservation and furtherance of our health. As dirt prevents t!)e access of air (§ 101), causes foul odours by decomposition and readily aids the germination of diseases, it should not be tolerated on our clothing; no more than on our skin (§§ 49, 50). Undercothing should therefore be fre-quently and thoroughly washed, and the outer garments should be daily brushed and shaken. The garments of others should never be worn without a thorough previous cleaning and linen should never be used, without a thorough previous washing.
110 B. The necessaries of life for the individual man.
substances, so that moisture and unhealthy exhalations from the earth may not penetrate into it. A clean, firm, sandy soil on a somewhat elevated position, which at the same time is favourable to the flowing off of the water forms a suitable site for building a house. If water is met with at. a small depth, it is necessary to drain it off by pipes. Where this is not possible it is advisable to line the foundation walls and basement of the building with suitable materials, such as asphalt or concrete, or to keep the water at a distance by so- called isolating walls. Such protecting walls to keep cellar- dwellings dry must be constructed of the most im-penetrable stones and cement mortar; they must penetrate deeper into the ground than the foundations of the building, and be separated from them by an air space several centi-metres thick.
Pollutions of the building subsoil must be removed by digging out the earth to a considerable depth and by re-placing it with good sand. Filling up the subsoil with dirt and refuse is highly objectionable.
The ingress of air and light must not be impeded by the position of the house. A dwelling house open on all sides is therefore as a rule preferable to a house built in a narrow street, although a site, which is protected against cold north-and biting eastwinds offers other indisputable advantages.
§ 113. Building- materials. As building· materials for dwelling-houses we use wood, natural stone (especially sand-stone, limesand-stone, marble and granite) or bricks, formed of clay and burnt. As cement for binding stones mortar is generally used, a material, composed of lime, sand and water, which quickly solidifies, and should dry in not too long a period of time.
For judging building material from the point of view of health, its porosity and dryness ought to be of decisive value.
By means of the pores of the walls a certain interchange takes place between the air of the house and the outer air.
This so- called natural ventilation (airing) which proceeds without artificial means, such as opening of doors, windows or ventilators supplies the occupiers of the house with a portion of their air.
Porous building material is therefore preferred, especially because porous walls in summer protect the house from the
direct summer heat and in cold weather best keep it warm;
for the air enclosed in the pores prevents the same tempe-rature existing inside and outside the house in the same way, as porous garments protect the body from chills (§ 101 ).
Of the building materials mentioned, limestone, wood, mortar, brick and sandstone possess more or less sufficient number of pores, which explains, why a wall, constructed of the latter stones always feels cold, unless directly heated by the sun. The above mentioned materials are therefore pre-ferred for the walls of a dwelling house, whilst marble and granite are most employed for ornamental palaces and statues or other monumental buildings.
Besides the porosity the dryness of the building material guarantees the healthy character of the house. Moisture closes the pores and thus lessens the quantity of air contained in the walls, and reduces their heat-retaining capacity; at the same time its inevitable evaporation contributes to further cooling. A damp wall therefore always feels cold air usually emanates from buildings, which are not yet dried. Moreover moisture favours the development of various classes of fungi, such as "dry- rot", whereby the durability of woodwork is endangered, damp air is produced in the house and a mouldy smell generated. Such fungus growth also pass over to the house utensils, bread, and other victuals and destroy them;
and it is not improbable, that the germs of many illnesses find in damp walls suitable conditions for their development and multiplication.
§ 114. Drainage and drying of the House. The roof.
The healthy dryness of a house not merely depends on the quality of the building ground and materials, but essentially on the certainty and thoroughness, with which the drying of the rough structure is effected. Before a building can be regarded dry in a sufficient degree, the greater part of the water, introduced into the walls with the mortar, the quan-tity of which is estimated at about 85 000 litres for a midd-ling sized town dwelmidd-ling house, must be evaporated. This process is quickest effected by a strong current of air and is aided in cold or damp weather by good stoves and by opening the windows. Only when the drying has progressed sufficiently, should the shell of the house be plastered and
112 B. The necessaries of life for the individual man.
further finished. 1) Even
a
completed house requires thorough airing and drying, before it can be inhabited without injury to health. 2)From a later injurious soaking of the house by the action of rain etc. the building is protected by plastering and paint-ing, which at the same time gives to the house a more pleasant aspect. Lime is used for plastering dwelling rooms.
Plaster of Paris is used for stucco work and combined with
"water glass" for the manufacture of external water proof linings, cornices etc. Among the means for effecting this, whitewash offers least resistance and oil colours the greatest resistance to the flowing in of water. All these coverings of the walls gradually succumb to the effects of the air by crumbling; they become moist and the water permeates them:;
they must be therefore renovated from time to time.
To a great extfint the roof of a building contributes a good deal to its dryness. Rain and snow should therefore nowhere in the roof find holes, but should be able to flow off freely over it and be quickly and completely carried off by pipes from the roof. As material for roofs in houses, the garrets of which are to be inhabited, tiles are especially suitable; for tiled roofs, which are laid upon rafters and joists, and are provided with a sufficient number of sheltered openings to insure a thorough ventilation of the lofts are the surest protection against dampness and cold. On the other hand, in rooms under slate and metal roofs the air is often close, in summer hot, and in winter difficult to heat. By their cheapness are recommended roofs from cardboard, strongly tarred over a framework of wooden spars, and roofs of so-called wood-cement, which consist of a thick mass upon a frame of boards, covered with fine sand or gravel.
§ 115. The final touches on a house. Floors. Walls.
In order to maintain a sufficient intervening layer between the floor of an upper and the ceiling of a lower room, so as to deaden the sound, as also to promote the preservation of heat, it is usual to fill up this space with the lightest, the
1) According to the police regulations in Berlin of 1897 at least six weeks are necessary for this drying out.
2) According to the police regulations in Berlin.- not before six months after the police certificate has been given, that the shell of the house is dry.
most porous, dryest and at the same time cheapest material.
If such filling material is polluted. with vegetable, or animal refuse, it may become the seat of foul-smelling decompositions, which allow repulsive and unhealthy odours to penetrate into the dwelling rooms; the use of contaminated filling-up material, particularly the use of building rubbish so freely employed formerly is to be avoided. Clean dry sand, coke- cinders, scoriae, peat or lime are suitable; still, even with these de-composable and putrid substances may penetrate through the joinings and cracks of the boards together with the sweepings, the scouring water and the dirt from the boots, if sufficient care is not taken to close the cracks in the floor. Where similar maladies reappear regularly in the same rooms dur-ing a long period of time, our thoughts will be turned to the possibility, that the germs of the disease have settled in the interstices of the floor, and can only be removed by renew-ing the fillrenew-ing it of the space between the two floors.
Wood is preferred.as flooring for dwelling rooms, as it keeps them warm better than a stonefloor, it is used chiefly as flooring boards or parquetry. A coating of paint or wax in-creases the durability of wood flooring and inin-creases the facility of cleaning it. Stone, ~ement and asphalt are more suitable for the floors of rooms, specially exposed to damp;
for instance bathrooms and laundries. If the floor of cellars are formed of these materials (cf. § 112), it is usual to lay a wood floor over them, but so, that a layer of air remains between the two floors, which keeps the cellar warmer and protects it from foul air.
For the purpose of preserving the floor from dirt as well as to deaden noise and to increase the warmth and comfort of the rooms, they are usually covered with thick impene-trable stuffs, such as carpets of all kinds, or linoleum, manu-factured with the help of cork. Carpets require to be fre-quently and thoroughly shaken, as they usually take up large quantities of dust, which may contain dangerous germs.
Carpets should be entirely removed from sickrooms, because infectious germs adhere to them and are spread by them.
Wall-paper is usually found as a covering for the walls of dwelling-rooms instead of whitewash or paint, and as a rule no objection can be made to its use, as it gives the rooms a more pleasant appearance and protects the walls
8
114 B. The necessaries of life for the individual man.
from damp and dust. On the other hand, wall-paper prepared from· heavy materials is a great absorber of dust and can be cleaned only with great difficulty. The health of the occupiers of the rooms may be seriously endangered by wall-paper, co-loured with poisonous substances, for instance arsenic.
§ 116. Utilization of dwelling-rooms. Air-space. Plan of the dwelling. Besides the character and structure of dwelling-rooms, the manner of their utilization is important for the health of the occupiers. The living of many persons in a narrow space injures the purity of the air, leads to the accumulation of dust and dirt and promotes the spread of infectious diseases. A dwelling that will answer the require-ments of hygiene must therefore possess a certain spaciousness.
Little value was formerly attached to that, and only in recent times the necessity of providing a definite amount of airroom for each occupier been recognised. As many large rooms, especially in old houses are insufficient for the air-require-ments of the occupiers on account of their low ceilings, the Berlin police building regulations prohibit the building of dwelling rooms with a smaller height than two and a half metres. Still the wish of saving space in private dwelling oversteps sometimes the limit, asked by hygienic laws, and the air-space of 15 to 16 cubic metres allowed to each German soldier in his barrack room is not at the disposal of many people in their private houses.
Unfortunately, economy compels many people to combine in one bedroom, workroom, dwelling-room and kitchen. In such cases, the occupiers, as a safeguard for their health ought at least to air and clean the room as often as possible.
Whoever is in a position to choose a larger dwelling should strictly maintain a division between the dwelling-rooms and those devoted to other purposes; in particular the bedrooms, the workrooms, in which relatively the largest part of the 24 hours of the day is spent, ought to be large, bright and airy.
§ 117. Ventilation. By sufficient space and a proper distribution of the particular rooms the quantity of air, ne-cessary for human beings in a room is not yet sufficiently supplied; there is required a constant airing in addition; a renewal of the air, rendered impure by breathing and perspi-ration in closely inhabited rooms. The usual fresh appearance of country people occupied in the open air, as opposed to
the ordinarily pale complexion of townspeople who spend the greater part of the day in closed rooms is a clear proof of the beneficial efl'ect of pure air on the health of the human body. Moreover the effects of a defective air-supply are often noticed in the fainting of weakly persons in church, assem-bly halls and theatres.
The change of air, necessary in houses is supplied to a certain degree by natural ventilation (§ 113) but by far the largest part of the air, required by
the occupiers must be provided by artifieial ventilation.
The simplest contrivances for this purpose are large doors and windows, provided with fans and ventilating panes. The regular opening of the latter preserves the air supply with greatest certainty; however in rooms, occupied by several persons at the same time, this process is generally displeasing to some, and is often therefore neglected, through exag-gerated precautions against draughts.
In addition, in many houses there are
air-passages leading from the outer Fig. aa
walls of the house into the rooms, Chimney cap for ventilation nCtc•·
1\'olpert.
and opening, some just under the door,
and some close under the ceiling, so as to bring in the pure air below and carry out the foul air at the top. The so-called "ventilator wheels" which force the air into such passages and exhaust it from them are used for the same purpose. Lastly, the chimneys of the houses are fitted with special caps (Fig. 33) so that the wind, blowing through them, draws up and carries away the foul air. During winter the renewal of air is facilitated by the heating apparatus.
§ 118. Purpose of heating. Requisites of a heating apparatus. The protection, afforded to the house by walls, floor and roof is not sufficient in cold seasons to prevent the air in the house from becoming cold, and the occupiers from the effects of frost. We therefore try by heating the house to replace the heat, withdrawn from it by the winter frost;
this is done partly by directly heating the air of the room 8*
116 B. The 'necessaries of life for the individual man.
by burning fuel; partly by introducing hot air, steam or water into the room.
The success of heating is greatly assisted by thick walls (cf. § 113) which conduct heat badly, as well as by tightly closing doors and windows, and particularly by double win-dows. The quantity of heat, given by various kinds of fuel is different; the heat, arising from combustion of coal gas is four times as great as that produced by burning wood; and between coal and wood, anthracite coal, charcoal, pitcoal and turf the capacity of giving off heat is in the scala just given.
The complete utilization of the heat, produced by the fuel depends essentially on the heating apparatus, as the latter may not only render the success of the heating doubtful, but also bring with it unhealtlty consequences. A serviceable heating apparatus must give off sufficient heat in a season of strong frost and still must admit of being regulated so, as never to overheat rooms, requiring heat. It should further diffuse its heat uniformly, and not produce the state of things so frequently observed, that the floor remains cold, while the upper strata of the air in the warmed room are excessively hot. The fuel must be consumed as completely as possible in the heating apparatus, without leaving behind large quan-tities of ashes. The smoke and gases of combustion should not penetrate into the room, but have a good draught to carry them off. The air in the house should always possess a certain quantity of moisture (§ 35) and therefore should not be dried up too much by heating. Finally risks, arising from the use of the heating apparatus must be quite excluded.
The injuries to health arising from defective heating ar-rangements are manifold. Colds and chills frequently occur among the inhabitants of unequally heated rooms; smoke in the room causes irritation of the eyes and headache; the gases of combustion, particularly the dreaded fire-damp, whose most dangerous component is carbonic oxide gas, frequently produce fatal poisoning.
§ 119. Fireplaces and iron stoves. We distinguish between apparatus for heating a single room and contrivances for heating an entire building. (Local v. central heating.)
The simplest arrangement for single heating is the fire-place (Fig. 34) which communicates the heat directly from the open fire to the room to be heated, and carries off the gases
of combustion up the flue without the help of a special chimney.
As heating by means of fireplaces requires a relatively large quantity of fuel, only heats the rooms sufficiently in the
neigh-Fig. 34.
I I *J
II I I I
I I
~i'i
Fireplace in front. Fireplace in vertical section.
bourhood of the fire, and does not prevent the smoke returning into the room, when the wind blows strong from certain di-rections, heating by stoves is universally preferred
in Germany. In these the heat is first commu-nicated to the heating surface, i. e. to the sides of the stove, and thence is distributed to the air of the room, to be heated. The remnants of the burnt heating material fall from the fire·
place into an ashbox through a grating. Smoke and the gases of combustion escape through the stovepipe into the flue.
The value of a stove consists in its capacity for utilizing the heat of combustion. The more
completely this is distributed to the heating sur· F ig. 35.
face, and the longer it is retained by the latter, eamwn ,1o•r.
the greater is the heating power of the stove.
The simplest stove is the so- called "cannon stove", (Fig. 35) whose heating surface consists of a simple iron pipe, resembling a cannon. This class of stove heats itself and