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Book I. (CONTINUED).
WHOEVER considers carefully the record of the medieval epidemics, and seeks to interpret them by our present knowledge of the causes of disease, will surely become convinced that one great reason why those epidemics were so frequent and so fatal was the compression of the population in faulty habitations. Ill-contrived and closely packed houses, with narrow streets, often made winding for the purpose of defence; a very poor supply of water, and therefore a universal uncleanliness; a want of all appliances for the removal of excreta; a population of rude, careless, and gross habits, living often on innutritious food, and frequently exposed to famine from their imperfect system of tillage,-such were the conditions which almost throughout the whole of Europe enabled diseases to attain a range, and to display a virulence, of which we have now scarcely a conception. The more these matters are examined, the more shall we be convinced that we must look, not to grand cosmical conditions ; not to earthquakes, comets, or mysterious waves of an unseen and poisonous air; not to recondite epidemic constitutions, but to simple, familiar, and household conditions, to explain the spread and fatality of the mediæval plagues.
GENERAL CONDITIONS OF HEALTH.
The diseases arising from faulty habitations are in great measure, perhaps entirely, the diseases of impure air. The site may be in fault; and from a moist and malarious soil excess of water and organic emanations may pass into the house. Or ventilation may be imperfect, and the exhalations of a crowded population may accumulate and putrefy; or the excretions may be allowed to remain in or near the house; or a general uncleanliness, from want of water, may cause a persistent contamination
of the air. And, on the contrary, these five conditions insure healthy habitations : 1. A site dry and not malarious, and an aspect which gives light and
cheerfulness. 2. A system of ventilation which carries off all respiratory impurities. 3. A system of immediate and perfect sewage removal, which shall
render it impossible that the air shall be contaminated from
excreta. 4. A pure supply and proper removal of water; by means of which
perfect cleanliness of all parts of the house can be insured. 5. A condition of house construction which shall insure perfect dryness
of the foundation, walls, and roof. In other words, perfect purity and cleanliness of the air are the objects to be attained. This is the fundamental and paramount condition of healthy habitations; and it must override all other conditions. After it has been attained, the architect must engraft on it the other conditions of comfort, convenience, and beauty.
The inquiries which have been made for the last forty years in England have shown how badly the poorer classes are lodged, both in town and country, and how urgent is the necessity for improvement. Various Acts have been passed for the purpose of improving laborers' cottages and other small dwellings, but either from the powers being insufficient, or from the difficulty of proving that a dwelling is injurious to health, unless it is in extremely bad condition, these Acts have had only partial effect.
Up to a certain point, there is no difficulty in insuring that a small house shall be as healthy as a large one.
The site and foundations can be made as dry, the drains as well arranged, the walls and roofs as sound, and the water supply as good as a house of much larger rental. In fact, in one respect, the houses of the poor are often superior to those of the rich, for the sewers do not open directly into the houses, and sewer air is not breathed during the night. But the difficulty in the houses of the poor is the overcrowding, and the impregnation of the walls with foul effluvia and deposits. Considerations of cost will probably always prevent our poor class of houses from having sufficient floor and cubic space. These two special difficulties must be met by improved means of warming and ventilation, and by covering the interior walls with a cement which is non-absorbent, and which can be washed. Perhaps, also, improvements in using concrete, or other plans, will eventually so lessen the cost of building that larger rooms can be given for the same rental, and the poor be taught to prize the boon of an abundant allowance of air, and not seek to lessen it by crowding and underletting.
Dryness of the foundation and walls of a house is secured by draining the subsoil, 4 to 9 feet below the foundation, and, in very wet clay soil
, by paving or cementing under the entire house. The walls are kept dry by being embedded in concrete, which is brought up to the ground level, or by the insertion in the walls themselves of a waterproof course of slate,
1 Laboring Classes Dwelling-house Act, 1866 ; An Act to provide better Dwellings for Artisans and Laborers, 1868; Artisans Dwellings Act, 1875; various clauses in the different Public Health Acts.
* Even the walls of old rickety cottages may be thoroughly dried by this means (Rogers Field).
• For a good diagram of a plan for avoiding damp, see Bailey Denton's Sanitary Engineering, Plate I., p. 56.
asphalt, or, what is better, of ventilating vitrified thin bricks (as devised by Mr. Taylor).
On wet damp soils, when a house has no cellar, the flooring ought to be raised 2 feet above the ground, and the space below should be well ventilated. In the tropics, the houses are often raised on arches 3 to 5 feet above the ground. If this plan were universal, it would vastly improve the health of the community. Dryness of walls is best secured by hollow walls,' or coating the walls with cement, which is kept painted, or with slates. Terra-cotta slabs have been used, and liquid preparations (chiefly alkaline silicates) have been brushed over the surface of brick and stone. Bricks are often extremely porous,' and a brick wall will absorb many gallons of water.
Dryness of the roof should be carefully looked to in every case, as water often gets to the walls through a bad roof, and the whole house becomes damp.
The condition of the basements or cellars, if they exist, requires attention, as the air of the house is often drawn directly from them. They should be dry, and thoroughly well ventilated, and the house pipes, if they run down to the basement, should be always uncovered so as to be easily inspected, and any bad-fitting joint, or crack, or imperfect trap, if there be one inside the house, be at once remedied.
The carrying off of rain water, so as not to sink into the ground near the house, is a matter of importance.
The other points which are necessary to secure a healthy house are discussed in their respective chapters.
In examining a house to discover the sources of unhealthiness, it is best to begin at the foundation, and to consider first the site and basements, then the living and sleeping rooms (as to size, cubic contents, and number of persons, and condition of walls and floors), ventilation, water supply, and plans of waste and sewer-water removal, in regular order.
The following memorandum as to the way in which engineers examine a house has been kindly furnished by Mr. William Eassie, C.E. :
What is usually done by Sanitary Engineers when inspecting a House.
Sanitary engineers consider that an unusual smell is generally the first evidence of something wrong, and that, traced to its source, the evil is half cured. They inspect first the drainage arrangements. If the basement generally smells offensively, they search for a leaking drain-pipe, i.e., a pipe badly jointed or broken by settlement, and these will often show themselves by a dampness of the paving around. If, upon inquiry, it turns out that rats are often seen, they come to the conclusion that the house drain is in direct communication with the sewer, or some old brick barrel-drain,
Jenning's patent Bonding Brick is a good plan for preventing moisture penetrating from the outer to the inner skin of a hollow wall. It is a hollow, vitrified brick, curved upward at an angle of 45°, so that no water can pass along it.
* An ordinary brick will hold about 16 oz. of water.
• Bricks imperfectly burned on the outside of the kiln are termed Place, or Samel, or Sandel bricks. They absorb much water. The sun-dried bricks of India are very damp, and absorb water from the air. Many sandstones are very porous ; water beats into them and rises high by capillary attraction. Lime made from chalk absorbs water. Pisé is compressed earth, and, unless covered with cement, is moist.
and therefore examine the traps and lead bends which join the drain-pipes to see if they are gnawed or faulty. If the smell arises from any particular sink or trap, it is plain to them that there is no ventilation of the drain, and more especially no disconnection between the house and the sewer, or no flap-trap at the house-drain delivery into the sewer. If a country house be under examination, a smell at the sink will, in nearly every case, be traced to an unventilated cesspool ; and, in opening up the drain under the sink, in such a state of things, they will take care that a candle is not brought near, so as to cause an explosion. If the trap is full of foul black water, impregnated with sewer air, they partly account for the smell by the neglect of flushing. If the sink, and kitchen, and scullery wastes are in good order and the smell is still observable, they search the other cellar rooms, and frequently find an old floor-trap without water, broken and open to the drain. If the smell be ammoniacal in character, they trace the stable-drains and see if they lead into the same pit, and if so, argue a weak pipe on the route, especially if, as in some London mansions, the stable-drains run from the mews at the back, through the house to the front street sewer.
Should a bad persistent smell be complained of mostly in the bedroom floor, they seek for an untrapped or defective closet, a burst soil-pipe, a bad junction between the lead and the cast-iron portion of the soil-pipe behind the casings, etc., or an improper connection with the drain below. They will examine how the soil-pipe is jointed there, and, if the joint be inside the house, will carefully attend to it. They will also remove the closet framing, and ascertain if any filth has overflowed and saturated the flooring, or if the safe underneath the apparatus be full of any liquid. If the smell be only occasional, they conclude that it has arisen when the closet handle has been lifted in ordinary use or to empty slops, and satisfy themselves that the soil-pipe is unventilated. They, moreover, examine the bath and lavatory waste-pipes, if they are untrapped, and if trapped by a sigmoidal bend, whether the trapping water is not always withdrawn owing to the siphon action in the full running pipe. They will trace all these water-pipes down to the sewer, ascertain if they wrongly enter the soil-pipe, the closet-trap, or a rain water-pipe in connection with the
If the smell be perceived for the most part in the attics, and, as they consider, scarcely attributable to any of the foregoing evils, they will see whether or not the rain water pipes which terminate in the gutters, are solely acting as drain ventilators, and blowing into the dormer windows. They will also examine the cisterns of rain water, if there be any in the other portions of the attics, as very often they are full of putridity.
A slight escape of impure air from the drains may be difficult to detect, and the smell may be attributed to want of ventilation, or a complication of matters may arise from a slight escape of gas. Neither are all dangerous smells of a foul nature, as there is a close sweet smell which is even worse. Should the drains and doubtful places have been previously treated by the inmates to strongly smelling disinfectants, or the vermin killed by poison, the inspectors of nuisances will find it difficult to separate the smells. In such a case, however, they will examine the state of the ground under the basement flooring, and feel certain that there are no disused cesspools or any sewage saturation of any sort. They will also ascertain if there be any stoppage in the drain-pipes, by taking up a yard trap in the line of the drain march, and noting the reappearance of the lime water which they had thrown down the sinks. And invariably, after ef
fecting a cure for any evil which has been discovered, they will leave the traps cleaned out and the drains well flushed.
A thoroughly drained house has always a disconnection chamber placed between the house drain and the sewer or other outfall. This chamber is formed of a raking siphon, and about two feet of open channel pipe, built around by brickwork and covered by an iron man-hole. Fresh air is taken into this chamber by an open grating in the man-hole, or by an underground pipe, and the air thus constantly taken into the chamber courses along inside the drain, and is as continuously discharged at the ventilated continuations of the soil-pipes, which are left untrapped at the foot, or at special ventilating pipes at each end of the drain. This air current in the drain prevents all stagnation and smell.
When a house is undergoing examination, it is wise to test for lighting gas leakages, and there is only one scientific method of doing so, which is as follows Every burner is plugged up, save one, and to that is attached a tube in connection with an air force-pump and gauge—the meter having been previously disconnected. Air is then pumped into the whole system of pipes, and the stop-cock turned, and if, after working the pump for some time, and stopping it, the gauge shows no sign of sinking, the pipes may be taken as in safe condition ; but if the mercury in the gauge falls, owing to the escape of air from the gás-tubes, there is a leak in them, which is discoverable by pouring a little ether into the pipe close by the gauge, and recommencing pumping. Very minute holes can be detected by lathering the pipes with soap and water, and making use of the pump to create soap bubbles.
Besides the drainage, they will, especially if they detect a bad and dank smell, see if it arises from the want of a damp-proof course or of a dry area, see if there be a wet soil under the basement floor, a faulty pipe inside the wall, an unsound leaden gutter on the top of the wall, or an overflowing box gutter in the roof, a leaky slatage, a porous wall, a wall too thin, and so on.
They will also keep an eye upon the condition of the ventilating arrangements, and whether the evils complained of are not mainly due to defects there. The immediate surroundings of the house will also be noted, and any nuisances estimated.
Sinitary inspectors, whilst examining into the condition of the drains, always examine the water cisterns at the same time, and discover whether the cistern which yields the drinking water supplies as well the flushing water of the closets. They will also ascertain if the overflow pipe of this cistern, or of a separate drinking water cistern, passes directly into the drain.
If the overflow pipe be siphon-trapped and the water rarely changed in the trap, or only when the ball-cock is out of order, they will point out the fallacy of such trapping; and, speaking of traps generally, they will look suspiciously on every one of them, endeavor to render them supererogatory by a thorough ventilation and disconnection of the drains.'
Much useful information will also be obtained from Sanitary Arrangements for Dwellings, by W. Eassie, C.E., and from Sanitary Engineering, by J. Bailey Denton, C.E. See also The Habitation in Relation to Health, by F. de Chaumont, Christian Knowledge series; Our Homes, and how to keep them Healthy, Cassell, Petter & Galpin.