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The total width of street is 36 feet, of which the roadway takes 24, leaving a footpath 6 feet in width on each side.

The surface of the finished roadway is a segment of a circle, the crown being level with the heels of the footpaths on each side; the formation surface is parallel with it, and of course the depth of this and the thickness of foundations and metal must depend upon local circumstances. It will be seen that the haunches are drained with 3-inch common drain-pipes. This may be omitted if the ground is thoroughly dry, but it is often a great help to a road.

The [paths], [kerbing], and [channelling] will be described in their respective chapters.

It must be borne in mind that on a perfectly level road a more convex section is necessary than on a gradient.

It is wrong to make the sides of a roadway weaker than the centre, especially in streets with shops on each side, or on hills where drags are likely to be used. On hills, too, be it remembered, the channels should take the surface water; any ruts from wheel tracks acting as watercourses are disastrous. Hauling timber on a macadamised roadway is also very damaging.

The great objections to macadamised roadways are as follows:—

(1.) They manufacture too much mud and dust.[23]

(2.) They are too absorbent.

(3.) They are very noisy and damaging to vehicles and horses when fresh metalled.