On Drainage and Sewerage of Towns. 369 
to point out the direction of the main sewer, which in one 
case would follow the bottom of the valley in which the town 
is built; while the North Esk River would form the main 
outlet for a large portion of the town,—the branch sewers 
being carried at once into the channel of the river. 
In many parts of Hobart Town the fall to the rivulet, or 
main outlet, is so rapid and short, as to render it probable 
that branch sewers of small dimensions would be amply suf- 
ficient to carry off, not merely the drainage from the houses, 
but also all the surface drainage of the streets; care being 
taken to provide against the risk of these small drains being 
choked by the accumulation of rubbish and mud from the 
streets. 
With regard to drains from the houses to the branch 
sewers, it is difficult to lay down any precise rules for the 
guidance of the engineer or builder. ‘These drains are a 
matter for the consideration of the owner of the property; 
and although law will step in to preyent any injury or 
nuisance which may be occasioned by the neglect or indif- 
ference of a proprietor, either to a neighbour or to the 
public, yet he must be allowed a great latitude as to the 
means which he may choose to employ to prevent such 
injury or nuisance. 
The same considerations which regulate the size of the 
branch sewers, namely, those which relate to the quantity 
of matter discharged through them, and the slope or fall, 
apply with equal cogency to house drains. 
It must be remembered that the smaller these drains are 
the more effective will be the scour of the water which ig 
passed through them, and an earthenware pipe of moderate 
dimensions will in general be quite adequate to party, off 
every thing, unless where the length of the drain is great 
and the fall but trifling, 
KK 
