either directly connected with the drains or connected with the
drains by bell traps. Of course this is a most dangerous state of
things. For when the top of the bell trap is taken off, an opening
into the drain is directly made. If the bell trap gets broken, no one
is told of it, and the drain is ventilated into the house for months.
On the other hand, if the top is left on and the bell trap is in a
place where water does not get into it continually, or at all, the
trap will get dry, and so become a ventilator of the drains into the
house; so that this plan of having ventilating pipes in the sinks, or
of having bell traps in the floor of basements, is most dangerous,
still more dangerous if the sinks are not used. Some think in this
way:--Oh! this sink is not used, there cannot be any harm in it! But
there is, and much more harm too. For the water in the trap dries up,
and so foul air comes into the house.
The sinks, then, ought not to be directly connected with the drains,
but should discharge through trapped gullies in the area; and not
only so, but the waste pipes of the sinks, whether upstairs or
downstairs, ought to have siphon traps, with traps and screws fixed
immediately under the sinks. These waste pipes are foul pipes even
when not connected with the drains, and if you do not have siphon
traps immediately under the sinks, foul air will come in, especially
during the night, and you will have a very serious nuisance caused in
the house in this way. The same remarks about cisterns upstairs apply
to cisterns in the basement. The water-closets in the basement are
simpler forms of closets, and they are very frequently supplied from
water cisterns by means of pipes which have merely a tap which you
may turn off or on. This is a most mischievous plan, as the cistern
may be emptied and foul air enter it. The closets in the basement,
therefore, ought to be supplied by means of water-waste preventers,
the best kind being the siphon-action water-waste preventers, which
discharge two gallons of water as soon as you pull the chain. These
“preventers” are not only to prevent the water being wasted by the
handle of the closet being fastened up, but also cut off the direct
supply of the closet from the drinking-cistern water.
_Grease Traps._--A much-discussed subject is the grease trap. In
small houses it is not needed; but in large houses, unless some
provision is made for catching the grease sent down the scullery
sink, the drains will soon be choked. Eassie gives a caution against
having the grease trap too large for its work, and as to the
importance of cleaning it out regularly, say once a week.
_Disconnection Traps._--Whether the house drains into a sewer, a
stream, a cesspool, or upon a piece of irrigation ground, one thing
which must never be omitted is a disconnection trap or chamber
between the house drain and the outfall. These traps--which should be
placed close to the house--prevent any smell from the outfall passing
into the house, and inasmuch as they have an inlet for the taking
in of fresh air between the siphon and the house, this fresh air
will course along the underground drains, and be discharged at the
ventilating continuations of the soil pipes, or at the tops.
[Illustration: 24. Disconnection Chamber. 25. Disconnection Chamber.]
Where the house is so large that the air inlet of these siphons would
not suffice, the latter are replaced by a chamber as shown in Fig.
24. The sewage flows into the air chamber formed by the half-open
pipe _a_, being ventilated through the grating _b_; thence it passes
through the siphon _c_ to the sewer in the direction of the arrow.
There is a raking entry into the sewer side of the siphon at _d_,
closed by a plug, thus preventing any smell from the sewer or drain
beyond the siphon entering the air chamber _a_. If the sewers are at
a great depth, the walls of the air chamber are made thicker, and a
manhole is built the length of the open channel, an arch being turned
over when the siphon is fixed, as in Fig. 25. The sewage passes from
_a_ through the siphon _b_ to the drain _c_, _d_ being the air inlet.
(Eassie.)
[Illustration: 26. Houghton’s Trap.]
One of the best modern traps is that introduced by Houghton (Fig.
26), in which the outlet _a_ at the bottom of the gully can be
pointed in any direction, and the inlet _b_ to the basin _c_ of the
gully, forming a movable half, can be turned round to accommodate the
entering waste pipe _b_; _d_ is the open grating which covers the
gully.
_Drains._--Tho drain itself is got at by opening down to it in the
front area. It may be found to be an old brick-drain, in which case
it ought to be taken out. Brick drains are pervious, they allow the
escape of foul air, and with contaminated air rats also get in the
house. Wherever rats can get, foul air can go; and rats coming in
through these holes may carry with them the poison of disease, such
as typhoid fever. Rats generally go to the larder, and carry with
them often the poison of such diseases, which are very largely
spread by their poisons being taken in this way by rats into the milk
and other foods, and also into the water in the cisterns.
Whether a brick drain or a pipe drain, it should be trapped before
it is connected with the main sewer or cesspool. This trap, in the
case of a brick drain called a “dipstone” trap, is a brick pit with a
stone across it from one side to another, and dipped into the water
which remains in the pit. The object of this stone is to prevent foul
air coming into the house. As a matter of fact, the pit holds a large
collection of foul matter and becomes a small cesspool, indeed, there
is no difference between them.
A drain may be made of glazed stoneware pipes, which may be joined
together in one of several ways. They may be laid “dry,” i.e. without
any jointing material between the ends, in which case they are, of
course, not water-tight; or they may have clay in the joints, in
which case you cannot fill them with water--that is to say, they
will not hold water under pressure. (If you fill them with water, by
plugging at the lower end, the water will come out at the joints.)
Or they may be laid with the pipes the wrong way. When the joints
are made with clay they will very soon become leaky; and when that
happens, the water oozes through the joints, filth collects in the
trap, and it gradually plugs up the whole drain from one end to the
other. This may go on for years without being found out, and so cause
the ground under the house to gradually become a large cesspool.
This is an extreme case. Or they may be jointed with cement, and
there are some other ways. They may be perfectly well jointed with
cement, so as to be water-tight. The drains, then, should answer to
this test, i.e. you should be able to plug them at the lower end,
and fill them with water. They should not be under the house, if
possible. In London we cannot help it as a rule. If under the house,
the straighter the course of the drain the better. Do not let it wind
about in order to get away from different rooms. The best thing is
to have a straight course through and to see that it is water-tight.
It should hold water like a teacup. The drain must not be directly
connected with the main sewer or merely separated by a siphon trap;
but there should be an air inlet into the drain between the siphon
trap and the house. This opening may be of different kinds. The best
kind is that of a manhole for access to the drain and trap (so that
the trap can be examined and cleared out at any time); the air inlet
should be a grating either over the manhole or in the nearest wall
opening into a pipe leading into the manhole.
People who are afraid of foul air coming out of these inlets put on
a valve with mica flaps, so that the air can blow in, but foul air
cannot go out. But, if there are no D traps under the water-closets
and sinks, if the pipes are straight and sufficiently large
ventilators are used, if the ventilating pipes go up above the roof
and are not protected from the action of the wind, you will never
find foul air coming out at the air inlet though you will find that
fresh air is drawn in. There can be no accumulation of foul air,
and the air that may be occasionally forced out is the last fresh
air that has entered. Should you, however, find foul air coming out
you will know that there is something wrong with the drain, that
the drain or siphon is plugged, so that this air inlet becomes most
valuable in pointing out when anything is going wrong.
Brick drains, says Eassie, are variously shaped. The worst sections
are those upon which two upright sides of brick have been built
upon flat stones, so as to form a bottom, and then covered over
with other flat stones, because the bricks can never joint tightly
with the stone, and there is always a leakage going on into the
surrounding subsoil. One great objection to brick drains is due to
the fact that they cannot be constructed sufficiently small to meet
the requirements of a house, and consequently are seldom found less
than 9 inches in diameter, which is far too large a sectional area to
properly drain a house.
However compactly and well-burnt the clay has been made into bricks,
a brick drain has only a certain life, so to speak, before its
decadence begins with the usual attendant danger. Its lifetime is
longer or shorter according to the subsoil in which it is placed,
the material used as mortar, the gradient at which it is laid, the
sewage which it removes, and the quantity of water, and especially
of heated water, which passes through it, but the consensus of
opinion in their disfavour for use in the interior of a house is
overwhelming, and a universal preference is accorded to drains
formed of earthenware pipes. A second objection to brick drains,
however well they may have been built, is their want of smoothness,
especially at the bottom, whereby the effete matters are not carried
easily away; and this want of smoothness is aggravated by the
roughness due to the unequal perishing of the bricks.
One of the first proofs of the perishing of a brick drain, making it
past redemption, is the appearance of rats. Rats will go always to
that place which affords them most food; and it is the brick barrel
drain which receives the washings from meat plates, and the grease
from the scullery pots, which rats most commonly frequent. They
will leave a drain, and nest themselves in the thatched roof of a
farmhouse, and they will form whole villages under the floors of a
town house. Rats generally find their way into houses by means of
holes which have been formed in brick drains by the falling down of
perished bricks from the arch, or owing to their having contrived
to make a passage through the brick drain above the usual wetted
perimeter. These rats, in the case of country houses, may come from
the stables, the barns, or the brooks; but in town houses they
chiefly emanate from the sewer. No matter whence originally derived,
they soon become habituated to a house and its dainty scraps, and
having once engineered their way thither, are seldom effectually
dislodged, especially in country residences. As fast as a hole is
discovered and stopped up, another is made by these persistent
vermin, until the foul air evolved from the house drain becomes so
distressful, and the rats so multiply, that some further steps are
necessary in dealing with them. Where the evil has not yet grown
formidable, traps are made use of, or poison; but this last is a
dangerous resource, as the rats are apt to die underground and emit
during decomposition, which lasts for months, the most horrible
smells.
It may be added that rats are remarkably clean animals, and will
never allow their fur to come in contact with anything that cannot
easily be immediately cleaned from it; hence, very often a dairy,
larder, or granary is surrounded by a trench outside the brick
walling to a certain depth, by broken glass and gravel, well grouted
with tar. Never rely upon a siphon trap in the drain, as a means of
keeping out these voracious and fast-breeding animals. They will eat
even through lead pipes ⅛ inch in thickness.
Having shown the necessity for discarding brick drains underneath
a house, Eassie next considers alternative clay-derived materials,
such as pipes formed of baked clay, after the latter has been worked
to a consistency which would not naturally allow of an escape of
their contents. There are, however, two or three subdivisions of this
class. First of all come those kinds whose ends are merely abutted
together, and not, as at the present day, socketed at the joints.
These are almost equally faulty with brick drains, because when
once they are poisoned and become the habitat of life-destroying
germs, their normal tone cannot possibly be recovered. The only kind
of earthenware drains which ought to be permitted inside a house
are glazed socketed pipes, well formed, well kilned, and properly
laid down, the whole of the pipes having been set on a concrete
bed, and afterwards covered over with properly made concrete, so
as to prevent any possibility of sewage reaching the subsoil, and
especially water-tanks. It is not every glazed socketed drain-pipe
that is fit for laying down, for the most abominably shaped pipes
are often met with. There are many makers beyond reproach, and
there are scores of pipes showing patent methods of jointing more
or less complicated. The majority of the improvements refer to the
fast seating of the ends of the pipes in cradles, well covered in
cement, and one especially much in use, Stanford’s, provides a ring
of material fitting truly upon a ring of similar material in the
socket of the pipe, so that when the two ends are put together, with
a little grease or resin between them, the pipes fit closely in every
direction, and require but little other luting. These pipes are
generally adopted for use under a house, and ordinary socketed pipes
for outside.
Cast-iron drains are now very often used in place of earthenware
pipes, and there is a great deal to be said in their favour,
especially since the invention of several processes whereby the
interior is prevented from rusting and scaling. Pipes of this
material are useful underground in rows of houses, and wherever
straight lines of delivery are obtainable, and compared with drain
pipes of earthenware, with their necessary surrounding of concrete,
they would prove not more expensive. Unfortunately, however, this
system cannot always be adopted, unless the house has been planned
with a view to this method of drainage; and in most houses it will
be observed that the pipes would have to run in front of fireplaces
and across doorways if above ground. When iron piping is used, great
care should be taken with the jointing, to see that it is properly
packed, and with material calculated to last as long as the pipe
itself. Iron pipes with merely leaded joints are subject to galvanic
action, whereby the iron, sooner or later, thins out by corrosion,
the iron perishing by “abnormal local oxidation,” as has been very
forcibly stated by B. H. Thwaite. When iron is contiguous with lead,
a galvanic action is set up, and, the latter being electro-negative
to the iron, the iron suffers. There ought, therefore, always to be
an assistant packing in the pipe, and the majority of engineers make
use of this. Eassie advises in addition, a luting of Portland cement
with the other materials, which may include a previous stuffing of
fibrous packing material together with the old-fashioned iron filings
and acids.
Given the best kind of drain to lay down, there is still the question
as to where to lay it, and here lamentable errors are frequently
made. The chief fault perpetrated in this particular is the laying
of drains inside a house, when they might just as easily have been
laid outside. When a drain is laid down, care is exercised to get the
pipes as much as possible in straight lines; and at each departure
from a straight line a manhole is formed, enabling any one to
inspect the drain at any time, by lifting the manhole cover. If a
lighted candle is placed at the bottom of the drain in the manholes,
the freedom of the drain from obstructions can be ascertained by
looking from manhole to manhole. These inspection chambers should be
placed at every departure from a straight line, and where several
drains junction together; thus each drain delivery is open to
sight, and rods can easily be introduced up the drain pipe should
any obstruction occur. These inspection chambers are always best
protected by an iron manhole cover, fitting down perfectly into their
iron frames, which are sunk into the stone floor.
Most houses in connection with a large brick sewer have a
“flap-trap,” just where the house drain enters into the sewer; this
flap opens to allow the house sewage to enter the sewer, whereupon
it should immediately close again to exclude foul air and rats from
invading the house. They sometimes, however, do not shut closely, and
in that case their action for good is almost at an end. A householder
can have an occasional inspection made of the trap by the sewer men,
by paying a small fee to the vestry.
_Precautions after Floods._--Dwellings which have been invaded by
the waters should receive special care, so that those whom the flood
has expelled should not occupy them before they have been made
sufficiently healthy for habitation. They should first be cleaned out
as quickly and thoroughly as possible, and freed from all dirt and
debris deposited in different parts by the water. Continuous aëration
and the most active ventilation are the best and most energetic
agents. To increase these as much as possible, where it can be done,
a large fire should be maintained on the hearth, and the doors and
windows opened, so that the light and heat of the sun may contribute
their part to purifying the air. At the same time care must be taken
to dig a ditch 10-15 in. deep around each house, whose interior is in
many cases below the level of the ground. It will also be well, after
having torn down all plastering, which will be in a bad condition,
to scrape to their bottom all joints in the walls, and to replaster
them in the parts of the house most injured, and where bad deposits
have principally accumulated. The floors, where such exist, should
be carefully attended to, and the soil under them covered with a
disinfecting substance, such as pounded charcoal, or sand, or else
with an impermeable material, such as flagging, paving blocks,
cement, &c. Where the house is several stories high, the top stories
should be the first occupied.
Great precautions should also be followed in the treatment of certain
articles of furniture, such as beds and mattresses, which must be
renovated or replaced, and which should never on any account be
used until thoroughly dried. Sanitary treatment, such as adopted
for houses, should be applied with no less vigilance to stables and
barns. One peculiar feature it is important to note, though it can
only be accidentally produced: it is the possible alteration of the
water of wells and springs of potable water, in whose neighbourhood
matter in a state of decomposition may have been deposited, or piles
of excrementitious and organic debris, or sources of water supply
which may have been contaminated by the contents of privy vaults.
Attention should be directed to this danger. To disinfect cellars
into which, by agency of the inundations, the contents of privy
vaults may have penetrated, commercial zinc sulphate may be used,
either by sprinkling it in powder in the cellar, or by watering the
ground when the water has gone down with a concentrated solution of
this salt. Concentrated solution of iron sulphate does well, but
the disinfection is not so complete as with salts of zinc; it is,
however, cheaper.
=Ventilation.=--The objects of ventilation are twofold--first to get
rid of the poisonous gas (carbonic acid) exhaled from our lungs, and
second to furnish a supply of life-supporting gas (oxygen, as it
exists in fresh air) to our lungs. For healthy living, every adult
individual requires at least 1000 cub. ft. of space, or a room 10 ft.
square and 10 ft. high; into this room should pass 3000 cub. ft. of
air every hour.
In dwelling-rooms, and especially in bedrooms, the fireplace should
always be left unclosed, and the flue or damper open for ventilation.
The windows should pull down from the top, and a piece of wire gauze
should be fixed along the open space at the top; or a pane of glass
should be perforated with holes capable of being closed in stormy
weather. All rooms, and especially sleeping apartments, should be
well aired during the day.
A good and simple test for impure air is to take a clear glass bottle
with a glass stopper, holding about 10 oz., and wipe it carefully
inside and out. On entering a room, the air of which you wish to
test, stuff a linen cloth into the bottle and rapidly withdraw it, so
as to allow the air of the room to enter the bottle. Then carefully
place a tablespoonful of clear lime water in the bottle, and replace
the stopper. Shake it for a few minutes; then, if the air is pure,
the lime water will remain clear. If bad, and loaded with carbonic
acid, the lime water will become turbid, or even milky. This is
because lime and carbonic acid together form chalk, which gives
the milky appearance. It must be remembered that this test has no
reference to the ammonia which often exists abnormally in the bad
air of towns, nor does it indicate the presence of disease germs or
poisons due to paint, wall-paper, &c.
A fire in an open fireplace is a good ventilator in a way. We may
ventilate a room easily by raising the lower window sash, and by
placing inside the frame a piece of wood 3-4 in. high, and 1 in. in
thickness, and reaching from one side of the frame to the other.
When the inside sash is brought down to rest on this piece of wood,
it is thus raised 3-4 in. A current of fresh air moves inwards and
upwards to the ceiling between the sashes, and if a piece of wood or
glass, sloping upwards, be attached to the top of the lower sash, the
current of air will be sent upwards to the ceiling, whence it will
diffuse itself through the room.
Draughts must be avoided; and it is wonderful how easily they may be
prevented. Pettenkofer has shown that if air at ordinary temperatures
does not move at a greater rapidity than 1½ ft. per second, its
movement is not felt. What is needed, therefore, is some kind of
screen that will not prevent the entrance of air, but that will break
its force, divide its currents, and make it flow unfelt into the room.
Perhaps the simplest plan of effecting this is the following: Open
your window at the top to whatever degree is necessary to prevent
closeness in the room, but if there is a draught open it wider still;
place a little loosely-packed cotton-wool between the upper and
lower sash, and in the open space above the upper sash place a strip
of perforated zinc, with its lower edge turned upwards, so as to
direct the draught towards the ceiling. If there is still too much
draught, open it still wider, but fasten in front of the perforated
zinc a screen of gauze containing loosely-packed cotton-wool. It is
noteworthy that there must be a sufficient current to carry the air
upwards along the slanting piece of zinc, and towards the ceiling,
otherwise, as Corbett has pointed out, the cold air will trickle over
the edge and cool the feet of the inmates of the room.
In the hot months it is worth while to bear in mind the plan adopted
by Martin in order to keep the rooms of the sick in a state of
freshness. This consists in opening the windows wide, and then
hanging wet cloths before them. The water, as it vaporises, absorbs
the heat, and lowers the temperature of the apartment by several
degrees, while the humidity which is diffused renders the heat much
more supportable. By adopting this plan, the inmates find themselves,
even in the height of summer, in a freshened atmosphere, analogous
to that which prevails after a storm. This fact is well known to
and utilised by the natives of India. Another plan is to close all
windows facing the sun and cover them with blinds or curtains, to
exclude the sun’s rays and the heated external air. Carpets may be
replaced by matting, and the latter may be sprinkled with plain or
perfumed water.