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hundreds of cases have come into my hands for investigation, where, upon examination, I have found the usual appliances, as though the drains, water-closet, and water supply had all been designed for the purpose of providing the house with an unlimited supply of typhoid fever. In these cases, notice must be served upon
the owner, requiring him to abate a nuisance, arising from a drain or water-closet so foul, for want of ventilation thereto.
The ventilation of water-closet soil-pipes, drains, and sewers, I am sorry to say, receives far too little attention at the hands of our local sanitary authorities; the water-closet soil-pipe should be continued, full size, to a few feet above the eaves.
There are some patent arrangements for these purposes, which may be seen at work in various parts of the country.
For particulars as to ventilating drains and sewers (a), which subject in itself would fill a larger volume than this, I would refer the reader to that first-class work, published by Baldwin Latham, Esq., C.E., entitled “Sanitary Engineering."
(a) As to ventilation in the metropolis (workshops and factories), see section 19 of Sanitary Act, 1866.
This is a subject that will require much attention and care at the hands of the inspector. The question on water for the examination for the Sanitary Institute may be fairly answered as follows:
Water should not be sparkling, as the chances are that organic matter is producing such sparkling effect.
Water should not have any offensive smell.
Water should not contain solid matter in suspension, and should be colourless.
There are many ways in which water will be found to be polluted, but the most prevalent one is the close proximity of a defective drain, and an offensive leaky ashpit and privy. This is a matter of quite common occurrence, to find the contents of a drain or privy leaking into a well from which the domestic water supply is taken (6).
In coming across such cases, action must be at once taken as provided by the 70th section, cap. 55, that is to say: take a sample of the water to the public analyst, and after receiving his certificate, lay it before your committee. If the water is polluted, intimate to
(6) As to polluted wells in the metropolis, see Sanitary Law Amendment Act, 1874, s. 50.
the owner (by circular preferred) that the 70th section requires you to summon him (the owner or occupier) before the magistrates to show cause why an order should not be made upon him, requiring him to close the said well; and further, intimate that if he is agree. able to do the work within seven days, you will allow the proceedings to be stayed in the meantime.
In sending water to be analysed, clean out well a quart stoppered glass bottle, fill with the water, seal it, and send it to the analyst the same day.
Lead service pipes should not be used for supplying water, inasmuch as under certain conditions they are likely to contaminate the water.
Shallow wells are not to be depended upon. When water is obtained from wells, they should be of sufficient depth to be free from surface soil water.
Great care must be exercised in the construction and arrangement of the pipes and fittings for the domestic supply, to prevent pollution. Water absorbs gases to a surprising extent, and on this account the overflow pipe from the cistern should discharge on to an open grate outside the main-wall, and not on any account be allowed to discharge direct into a fall pipe or drain, or water-closet soil-pipe.
The following suggestions, extracted from “Suggestions as to Main Sewerage, Drainage, and Water Supply,” by R. Rawlinson, Esq., C.E., C.B., will be found to be of service to the inspector, containing, as they do, the result of a large and important experience:
The general principles of water-supply may be stated briefly as follows :1. To select the purest available source after careful
analysis. 2. To filter the water, if necessary, in order to free
it from suspended matter and from dissolved
organic matter. 3. To store it in covered tanks, and to raise it a
sufficient height for distribution by gravitation. Applying these principles, water may be obtained From rivers and streams.
By means of open conduits (before filtration).
tion. By means of cast-iron pipes under pressure. Where a district is to be supplied with water, all other things being equal, the softest and purest water should be adopted.
A water-supply may be gravitating, or the water may be pumped by steam-power. The relative economy of one or the other form of works will depend on details of cost and quality of water. As a rule, gravitating works require the largest capital. The annual working expenses of a pumping scheme may, however, be granted.
Reservoirs, for service distribution, should be covered.
If filters are used, the water should not be exposed in open reservoirs and tanks after filtration.
Cast-iron pipes, properly varnished, should be used for street-mains. It is not advisable to use mains less in internal diameter than three inches.
Lead should not be used with soft water, either in service pipes or in cisterns. Wrought-iron tubes with screw joints may be used for house service. All house taps should have screw joints, and be of the description known as “screw-down," so as
screw-down," so as to admit of easy repairs.
In jointing and fixing wrought-iron service pipes care should be taken to insert double screw joints at convenient points, to allow of the removal of a length of pipe for alteration and repairs.
Wrought-iron service pipes are cheaper, stronger, and more easily fitted than service pipes of lead. Certain sorts of made ground, in towns, act rapidly and injuriously on both lead and iron pipes, such as furnace ashes, waste gas, and chemical refuse, old building refuse containing lime. Pipes should not be laid in such material without a lining of sand or puddle, or other special protection (a).
(a) Wrought-iron service pipes for gas are laid in a wooden trough V-shaped, which is filled with asphalte around and over the pipe so as to protect it from the subsoil. Some of the London gas companies protect wrought-iron pipes in this manner.