This section is from the book "Health", by W. H. Coefield.
If not got rid of they produce disease, and in every place where refuse matters are not got rid of speedily, there is a high death-rate, and especially a large proportion of deaths among infants.
These refuse matters get either into the water which is drunk, or into the air which is breathed, or into both, and cause a general low state of health. The effects on the death-rate of infants are bad, because infants are peculiarly susceptible to disorders caused by foul organic matters. Cholera and typhoid fever are diseases which especially prevail in communities where the refuse matters are allowed to accumulate in and about the houses.
There are a great many plans by which refuse matters are removed from houses and from towns. There are, however, two particular systems-the first of which goes by the name of the conservancy system, and the second by that of the water-carriage system.
The name of the conservancy system condemns it at once-I have told you it is of the first importance for the health of the community that refuse matters should be removed from habitations-as it shows that the very principle upon which this system depends violates one of the first laws of health, viz., that refuse matters ought not to be kept or allowed to accumulate in the neighbourhood of habitations.
A great many plans have been tried: sometimes refuse matters are collected, as in Edinburgh, without anything being mixed with them at all; sometimes they are collected and mixed with the ashes provided by the fires ; sometimes they are collected and mixed with dry earth, according to the dry earth system brought into notice by the Eev. Henry Moule; sometimes they are collected and mixed with a deodorising or disinfecting substance ; but whatever the plan is there is the same mistake all round-they are kept in or about the houses as long as they are not a nuisance ; that is the theory upon which these methods all go. It is essentially a wrong principle; in a certain .number of instances they will be kept until they are a nuisance, and necessarily kept, therefore, until they are poisonous. And you can see, also, that an enormous disadvantage in these systems is the expense of cartage -the expense of carrying the refuse matters away ; and in the case of the dry earth system there is the additional expense of collecting the earth, drying it, and carrying it into places that are to be supplied. You can see at once, for these systems to work economically, it is advantageous to leave the refuse matters in and about the habitations as long as possible, because the less it is necessary to send round carts to collect it, the less expense the arrangement will entail; so that all these plans, if they are carried out economically, are more likely to be injurious to the health of the community ; and in all towns in which refuse matters are disposed of in this way, although it may happen that the system as now carried out is better than the systems which were carried out ten years ago, still in all towns where refuse matters are left for a certain time, and carried away bodily, there is a high death-rate, and a comparatively low condition of health. Now, these systems, including the dry earth system, are none of them fit for towns, but they are suited, under certain circumstances, for small villages, and for large temporary gatherings, such as cattle-fairs, horse-shows, etc., and for places where special and particular attention can be given to them; but they are not suited for use in the midst of large collections of human beings.
We will pass on to the consideration of the system which is in use in London-the water-carriage system. With any system you must have pipes to get rid of the foul water, and in ninety-nine out of a hundred cases it is a great advantage to get rid of all refuse matters at once, and for that reason the water-carriage system commends itself.
One of the reports from India on the dry earth system, which has been carried out there very largely, states that in every well-organised community-they are speaking of barracks, and what is true of them is also true of houses and towns-the foul water that has to be got rid of is to the refuse matter that can be removed by the dry earth system as 190 is to 1. It is perfectly absurd to have two systems, one to carry away foul water, and another to carry away foul refuse matters, bearing the proportion of 190 to 1. Foul water has to be got rid of from houses, and so we must have pipes to get rid of it. These pipes we call sewers. The foul water must not be allowed to get out of the pipes into the soil below the houses, and so they require to be made water-tight; it will not do to have the sewers below the houses (commonly called the house drains) made of bricks, or other pervious materials, as was the case with all the old house drains of the metropolis. Drains or sewers to carry away foul water require to be impervious in order that the water may not get out into the soil; they are now commonly made of the material known as glazed stoneware, with socketed joints carefully cemented; thus the foul water can get away from the houses by these pipes without getting into the soil underneath, and without getting into the water if the house is supplied by a well.
The pipe that conveys foul water away from the house must end in the common sewer of the district, and where it joins the street sewer a very common plan, and not at all a bad plan, is to put a heavy metal flap hung on hinges at the mouth of it; the foul water running down from the house pushes open the flap and falls into the sewer, but as soon as it has done running, the flap shuts. That simple contrivance works very well so long as it is in order, and it can be examined from the inside of the sewer ; it is used very largely in London.
Upon the house sewer it is usual to put some kind of water-trap. Now, the water-trap, whatever be its form, and there are a great many varieties, is essentially a bend in a pipe which will hold water; the simplest is the so-called syphon, or U shaped bend; when water is poured down it will remain in the bend up to a certain level, so that the water will prevent air from coming into the house through the pipe, from the sewer. But remember always this, that water-traps are things that cannot be relied on: they will prevent great draughts of air from coming out of the pipes when there is water; but suppose there is water in them, then foul matters in the air on one side are absorbed into the water and given out from the surface on the other side into the house ; that has been shown perfectly clearly by experiment. Matters of various kinds can be absorbed on one side of the water-trap and given off on the other side, so that you cannot rely upon water-traps alone to prevent foul matters in the sewers getting up into the house. You must rely on something else, and that is ventilation, a means of escape, or, if possible, a forced escape, of the air from the sewer into the open air, so , that from every house sewer there ought to.be one or more four-inch pipes rising up outside the house from the highest points of the sewer, and going above the tops of the houses into the open air. These pipes may be continuations of the soil-pipes, but must not be rain water-pipes unless the top of these pipes is at a considerable distance from any window.