improvements can in future be made. The idea of carrying tall
ventilating pipes to the tops of houses was to carry off gas that was
forced in bulk through the trap at the bottom of the soil-pipe from the
sewer, but in well-laid drains this should never occur. If the drain be
disconnected it would leave at the point of disconnection.
The velocity of the water rushing down the pipe, as proved in the
previous chapter on drain testing, carries the gas out at the bottom of
the pipe, the top of the pipe forming the inlet when odours are given
off from the passing soil, but as soon as the flushing is over a return
current takes place and fresh air ascends the pipe.
If you do not use any method of purifying the gas which escapes through
the pipe, the best plan is to have the pipe as open as possible at the
top and bottom, and at all bends, for ventilation. These openings need
only be just above the level of the water flow to prevent splashing, and
by following this rule those unsightly pipes (which give buildings more
the appearance of a distillery or chemical works rather than a
dwelling-house or home) can be avoided and erected so as to form one of
the ornaments in the architecture of the building.
There is at present too much theory in sewer ventilation, without paying
any attention to results gained, or to the laws which control the
atmosphere and its action on sewage matter.
THE ORIGIN AND TRANSMISSION OF ZYMOTIC DISEASE.
Whilst making experiments and taking observations five years ago, to
trace the origin and transmission of some cases of zymotic disease, I
formed an opinion that the theory as regards the transmission of zymotic
disease by contagion was to a certain extent an erroneous one.
I mentioned this to some of my medical acquaintances at the time, but as
it was so opposite to the prevailing ideas, I was advised not to publish
or hold out such opinions, as they were contrary to the theories
accepted by the medical profession.
Now that these theories have been severely shaken, and in many cases
reversed by medical men themselves, during the past year, I shall plead
no excuse, but insert them for the guidance of those engaged in sanitary
work.
The source of zymotic diseases may be traced to persons inhaling or
taking into the system poisons from putrid sewage matter, and those
poisons are conveyed into the body, either in the food they eat, the
water they drink, or the air they breathe. Whether they are organic or
inorganic, they poison the blood, which becomes more or less diseased,
according to their density or vitality, or whether each of the zymotic
diseases is produced by distinct organic germs grown and developed from
putrid matter under different atmospheric influences, it matters not to
my mind in proving the true method by which zymotic diseases are
transmitted.
On the origin or source from which these diseases are produced, I do not
think there are two opinions, viz. that of poisons from putrid matter,
and the question to be solved is in what manner these poisons are
conveyed into the system. To do this it will be necessary to quote some
cases of zymotic disease and the circumstances which surrounded them.
In a small district, a girl thirteen years of age was taken with
diphtheria, and in two days after the younger brother was taken and the
other children appeared sickly. From investigation it was certain that
the poison had not been conveyed into the system by food or water. The
children generally took their meals in the kitchen, the door of which
opened into the yard, which was about 10 feet long by 8 feet wide, in
the corner of which was the W.C. I tested the atmosphere entering the
room at the bottom of the doorway, and found that it contained poisonous
matter, and on testing the closet and drains I found a hole 3 inches by
¼ inch in the closet trap. Here was the source of poison which produced
the disease. The gas in the drain was confined between two traps and in
contact with putrid sewage matter, and when it was removed no poison
from any other source could be detected. The first child that was taken
ill died, but the other recovered.
Now it is quite evident that the second child did not take the disease
from the first, as it had not time to develop. The atmosphere of the
room and the breath of the child were not as poisonous as the atmosphere
of the kitchen in a line between the kitchen fire and the door, and it
was on this line both children sat at their meals, and thus inhaled the
poison with their food. Had the gases in the other drains of the
district been of the same density as in this one, and similar leaks
existed in the sanitary fittings, diphtheria would have spread, and by
the popular theory its transmission would have been attributed to
contagion from this family, which in face of the above facts would have
been incorrect.
Another case. In a large town diphtheria broke out, and some hundreds
were attacked and over two hundred died. The source of the disease was
not in the food or water, and the only disease-producing poison that
could be found was in the gas issuing from the sewer gratings and
sanitary fittings. Schools were closed and the usual remedies used to
prevent contagion, but all to no purpose. The sewers being of an easy
gradient had silted, forming at intervals masses of putrid matter, and
in the best houses, where the disease was most prevalent, poisons from
the sewers were laid on to them by the badly-constructed drains and
sanitary fittings. The authorities at last took the matter vigorously in
hand, cleansed and sweetened the sewers as much as possible, and then
the disease abated and died out. Had contagion been the means by which
the disease was transmitted, it would have continued as it existed in
the town under almost every kind of atmospheric temperature.
Here we have evidence showing that putrid matter did exist from which
poisons were given off and their mode of transit into the body, but not
the slightest evidence to prove the poison passed direct from one person
to another.
These poisons in the gas can be destroyed by washing the gas in a
chemical solution on leaving the grating, and since this has been done
medical men have cured the disease by washing the throat in a similar
solution.
Numbers of typhoid cases could be mentioned where poisons from putrid
matter were conveyed into the system by water, milk, and impure food,
but I have never heard of a case where the poison was detected leaving
one person for another.
If in 1883 a person had stated that cholera was not contagious, they
would have been ridiculed, yet the principal physician and those in
charge of the cholera hospitals of Paris last year, certified to the
representative of one of our daily papers that cholera was not
contagious. The cholera epidemic of last year proves that cholera
poisons are produced by heat and atmospheric influences on putrid
matter, and circumstances favour the theory that they are inorganic, and
when inhaled into the system poison the organisms of the blood to such
an extent as to produce the disease. Cases of cholera broke out in
different parts of the Continent at the same date, clearly showing that
contagion had nothing to do with producing or transmitting the disease.
In England our ports were jealously watched to prevent any case from
being landed. Had a case been landed, the excreta from that one case
might, when mixed with the sewage of a large town, have been the means
of spreading the disease through the whole district, as miles of sewers
are so laid that poisons in the gases can be effectually distributed
through the district in a very short time. Open ventilation to sewers
would greatly assist this, and especially when the gases in the drains
and the fresh air admitted into them were of a high temperature. It is
very improbable that cases if imported would break out in two towns at
the same time, or that the poison could be conveyed in the atmosphere
which divides us from the Continent.
Fortunately, when the continental outbreak was known, the authorities in
the metropolis and other towns used disinfectants on all known putrid
matter, and especially at the sewer gratings. This was an expensive
process, but it had the effect of preventing the atmospheric influences
(which were similar to those on the Continent) from developing the
poison to a vitality necessary to give the disease.
It would be an excellent preventive if the authorities of towns would
thoroughly examine every part of their districts, and know for a
certainty whether in their sewers, cesspits, vaults, or dust-bins there
existed putrid matter, or gases from them similar to those which
produced the disease on the Continent. The expense of such an
examination and for remedying the evils cannot be an excuse for not
doing this work, as the monetary loss experienced by the residents of
those continental towns and cities by the outbreak was enormous. What
the loss would be to the residents of the metropolis if a cholera
epidemic were to occur, it is difficult to imagine, and yet in many of
the districts cholera-producing elements exist from which in all
probability the heat and atmospheric influences experienced during
several weeks of excessive dry weather during the summer months will
produce poisons of a similar vitality to those produced on the Continent
during the past year.
Previous to the cholera epidemic, small-pox was very prevalent in
London, and I very carefully noted the cases as they were reported, and
visited the districts where the disease was most prevalent, for the
purpose of testing the nature of the gases in the sewers, and observing
how the sewers and sanitary fittings were constructed.
In many of these districts, and especially those of Homerton, Hackney,
Bow, and Bromley, the drains are so laid and the fittings so constructed
that a supply of sewer gas is pumped into the houses, and it is
impossible for persons to live in the houses of these districts without
inhaling gases that have been for a long time in contact with sewage
matter.
Whether the small-pox poison is an organic one (which I believe it is),
and is produced from a collection of matter in a high state of
decomposition, with or without being mixed with the excreta of persons
suffering from the disease, or whether it is of an inorganic nature, the
poison is derived from this source rather than from the impurities
thrown off through the skin of persons suffering from the disease. As a
proof of this, as soon as the cholera broke out last year on the
Continent, almost every gulley and grating in the metropolis where sewer
gas passes was charged more or less with a disinfectant, which minimised
the poison in the gas. The result was that small-pox abated in an
epidemic form although the temperature of the atmosphere increased.
The disinfectants so placed could not, naturally, affect the gas in
branch drains to houses, or putrid matter in various parts of the
sewers, or if it had, judging from its beneficial effects at the
outlets, small-pox would have disappeared.
If contagion were the means by which this disease was distributed,
disinfectants at sewer gratings would not have prevented the disease
continuing in an epidemic form.
Take the adjoining districts of Fulham and Putney. During the epidemic,
the gases from the sewer gratings in the Fulham district were more dense
than those at Putney. Fulham had many cases of small-pox, but Putney
none, although persons from each district were in daily contact with
each other; but the houses were not connected by the same system of
sewers.
It must not be thought that I wish to advance the theories of the
anti-vaccinationist. I have had my children vaccinated because it is the
law, and in the opinion of medical men a preventive against the disease,
but viewing the change of medical opinion with reference to cholera
during last year, and comparing tests and observations that have been
made, they will soon be convinced that vaccination is a futile remedy to
use with a view of stamping out the disease.
At present the question is (with medical men) one of theory, but ere
long I am certain that they will take a more practical view of the case
and definitely fix the origin of this disease and its distribution.
Previous to vaccination being introduced, putrid matter in vaults,
cesspits, and drains was allowed to reach a higher state of
putrefaction, and thus the poisons from them became more virulent and
produced the disease of a more virulent type.
If modern systems of drainage and sanitary arrangements were the means
of preventing this high state of putrefaction, and of reducing the
disease to a milder form, perfecting these arrangements should be the
means of stamping it out altogether and rendering vaccination useless.
Unless it can be proved that poisons given off through the skin and from
the lungs of persons suffering from the disease are as virulent as those
from putrid matter alone, or from the excreta from those suffering from
the disease, the theory of contagion[2] cannot be entertained.
Footnote 2:
The word contagion as here used is not intended to apply to cases
where persons not affected sleep in the same bed, or wear the same
clothes, or handle things from, or persons suffering from this
disease, as this would be inoculation.
Many medical men will say that the facts to prove that small-pox is
transmitted by contagion are so positive that there is no chance of
disputing them.
Let us examine two cases to support this theory.
Small-pox is prevalent, say, in the north of London; a man is in
business there from seven to eight hours each day, but his home is in
the S.W. district. He is taken ill, and remains at home, calling in his
medical attendant, who on his second visit pronounces it a case of
small-pox, and orders his removal to the hospital. In a few days other
members of the family are taken and removed, and similar cases occur in
the neighbourhood.
The theory of the medical man would be that his first patient had
contracted his disease in his place of business in the N.W. district and
had conveyed it to the S.W. district, distributing it in the
neighbourhood in which he lived. This is only theory, and the only thing
the medical man has to rely on to prove his case is, that the man first
taken was engaged three-fourths of each day where small-pox was
prevalent. Against this theory, assume that the disease originated by
the whole of these persons inhaling poisons from putrid matter in their
own locality or at their own doors, or in their homes, but that the
atmospheric influences to develop the poison was a few days longer
completing its work in the S.W. district than in the north. Then test
the sanitary conditions of both localities, and you will find similar
matter producing poisons. These are facts that will support this view of
the case, as well as the following evidence which cannot be
contradicted. When sewage matter is allowed to remain in bulk
undisturbed, and in connection with a system of sewers, it forms retorts
for the generation of these poisons, and they are conveyed for miles in
drains by atmospheric and other influences; and where these people lived
the gases would probably be discharged with a greater facility than at
any other point.
Take another case. A man leaves London for the country, and a day or two
after his arrival he is taken ill with small-pox. There is no system of
drains to the house in which he is located. People living in this and
other houses are affected with the disease, and the medical officer of
health in his report states that the disease was conveyed from London to
the district by this man. He was certainly the first one affected, and
at first sight this case appears to be conclusive in favour of
contagion, for if he did not contract the disease in London and bring it
into the country how was it that he was first affected?
It is certain that putrid matter from which the poisons are derived
exists in villages similar to that in towns, consequently the poisons
are there, and medical men agree that when a person leaves one locality
for another, for what is commonly called a change of air, the system
undergoes a change. This change had such an effect on the system of this
man that the poison from the putrid matter of the village had a greater
effect on him and poisoned the blood more quickly, than on those who
were inhaling the poison during its various stages of development: but
when it was fully developed by atmospheric influences the disease
appeared in those other persons who were in contact with the poison.
The action of sewer poison on the system is similar to that experienced
by persons taking cold. Persons occupied in rooms which have an equal
temperature, or are not subjected to cold chilly winds, take colds and
contract all sorts of complaints on being exposed to currents of cold
air even for a short time. The draught from a window only, when a cold
stream of air is playing upon it, will do this: the blood is chilled,
hence the cold, fever, or one of the many complaints follow; but on
persons used to exposure it has no effect. In the same way sewer poisons
act on those who suddenly inhale them, only the blood becomes poisoned
instead of chilled; but on those who are in constant contact with them
they have not such an effect, yet on these persons the effect of them
can be traced.
The medical profession have hitherto placed too much reliance on
isolation as the sole means of stamping out this disease.
The Metropolitan Asylums Board have had ample means at their disposal
since 1867 to test the soundness of this theory, yet after spending
something like 480,000_l._ per annum, small-pox has increased 100 per
cent. since that date! This fact alone is sufficient evidence to prove
that other means than those of isolation must be used to effectually
stamp out this disease.
It is of little use to have elaborate arrangements in hospitals and
camps to minimise the effects on persons who have taken the disease, and
at the same time allow the source from which it emanates to remain
undisturbed. I admit that it is a question too complicated to be
exhaustively dealt with in a work on the testing of drains and sanitary
fittings, but it is inserted to show what a power those who are engaged
in designing or executing sanitary works hold for good or evil in
affecting the health of the community.
Experience proves that ninety-nine zymotic cases out of every hundred
are caused through imperfect sanitary works and appliances.
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