SECTION III. 

 SANITATION. 



THE hygienic disposal of excreta and other solid and liquid 

 waste material is a matter of great importance, as the health of 

 both man and animals is dependent to a very large extent on the 

 efficiency of the method adopted. A system of pipes for the 

 removal of refuse, either liquid or rendered more or less liquid by 

 the addition of water, from a habitation constitutes a drainage 

 system. As liquids which have to be conveyed away are for the 

 most part foul, open channels are unsuitable and pipes of some 

 form must be used. A drain is a pipe or channel used for the 

 conveyance of liquids. The object of a drainage system is to 

 convey the refuse from the various points of origin to the public 

 sewer or other point of outfall as rapidly as possible and in such 

 manner as to cause no inconvenience or nuisance. 



In the case of a house it is usual to classify the liquid refuse into 

 three classes: (1) Soil; the discharge from w.cs., urinals and 

 slop sinks. (2) Waste : the discharge from sinks, lavatory basins, 

 baths and wash tubs. (3) Rain water. A drain is a soil drain 

 if it takes the discharge from a soil fitting, no matter how much 

 waste and rain water it also conveys. A rain water drain conveys 

 nothing but rain water. In the case of animal habitations there 

 will only be two classes, soil and rain water. 



A drainage system should be simple and as free as possible from 

 complicated traps and other fittings. The number of pipes in a 

 system must be reduced to the necessary minimum. Pipes should 

 be laid in straight lines so far as possible, and access should be pro- 

 vided at all the principal changes of direction. Pipes must be of 

 such capacity and laid at such a gradient as will render them self- 

 cleansing. Special attention must be paid to junctions. The entire 

 system must be thoroughly ventilated, that is, air inlets and outlets 

 must be so arranged that fresh air can find its way to every part 

 of the system and so ensure that at any time the pressure inside at 

 any point is atmospheric. 



DRAIN PIPES. Drain pipes must possess strength to withstand 

 the pressure of the superimposed soil and the weight and jar of 

 traffic. Strength is also necessary to resist the internal pressure of 

 gases, though this should not be great in well-ventilated drains. 



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