into holes or ruts, even if formed of the very 
best materials, and the greatest pains should be 
taken for its preservation. For the same rea- 
son, a good road is scarcely ever met with in 
a thick wood, merely because the foliage shuts 
off the sun’s rays, and by excluding them, 
and a free circulation of air, prevents that 
evaporation that would otherwise take place. 
Perfect drainage must therefore be considered 
as the great and leading requisite to the exis- 
tence and maintenance of a good road, and this 
ought therefore to be the great object of attention 
to the engineer in the setting out new roads, and 
the amendment of those that already exist. It 
may frequently be difficult of attainment, espe- 
cially in level countries; but we will endeavour 
to give such directions as seem most likely to 
assist in attaining this most essential object. 
No road should be formed in a hollow or con- 
cave form, or even be quite flat upon the surface 
of its transverse section, but, on the contrary, 
should be convex or protuberant along its cen- 
tral line. If the centre of a road of 20 feet wide, 
is made 6 inches higher than its two sides, this 
will keep the middle dry, by throwing the water 
to the two sides, This rising or convexity in the 
centre, is called the crown of the road, and as 6 
inches is the twentieth part of 10 feet, or the 
half-width of the road, the crown would be said 
to rise 1 in 20, and a proportionate elevation 
should be given to the transverse section of every 
road, whether it is narrow or wide. Such a con- 
vexity will occasion no danger to carriages run- 
ning upon it, or any inconvenience. If such a 
road is above the level of the adjacent land, the 
water may be discharged from its two sides with- 
out inconvenience, or it may be conveyed into 
ditches sunk on the sides of the road and run- 
ning parallel to it. In level countries, difficul- 
ties may arise in getting the water discharged 
out of these ditches, and they may require to be 
made very deep in the progress of their fall; still, 
it seldom happens, but that a vent or discharge 
of some kind may be discovered in the progress 
of a few hundred yards; and, should that prove 
impossible, ponds or reservoirs may be sunk in 
the lowest pieces of land that can be found, in 
which the water may sink into the land, or be 
dissipated in evaporation. A very small fall or 
descent will be sufficient for road ditches. They 
should begin at the surface, or have scarcely any 
perceptible depth at the upper part of the road, 
and become gradually deeper and wider as they 
descend ; and all the soil dug from such ditches 
should be thrown on to the road to elevate it, 
instead of being thrown on the outside of it, as 
frequently practised. 
Whenever it may be necessary to sink deep 
ditches by the side of a road, they ought always 
to be separated from it by a foot-path or cause- 
way, raised from nine to twelve inches at least 
above the road, to prevent accidents to cattle or 
carriages that might fall into them; the water | 
in this case being conveyed from the road by 
drains passing through such causeway; and, 
whenever for the purpose of drainage, it may be 
necessary to convey water from one side of a 
road to the other, it should always be carried by 
a drain or brick culvert running under the road, 
and in no case be allowed to flow freely over its 
surface. 
A perfectly level road is by no means desira- 
ble, on account of its property of retaining water; 
and, as a very slight slope or inclination in the 
longitudinal direction will be sufficient to pro- 
duce a discharge of water to the lowest part, 
while it will hardly be perceptible in its effect 
upon the draught of carriages, so it ought always 
to be obtained. By a judicious selection of line, 
and setting out of a road, sufficient slope may 
generally be found on the natural ground; but 
if that is impossible, it must be produced in the 
earth-work, that is to say, in the slight cutting 
or excavation that is always necessary for ren- 
dering the surface of the ground smooth and 
uniform, and fit for the hard materials that have 
to be laid upon it; and by distributing the soil 
that should be excavated from one or both sides, 
for draining ditches. Instead of throwing the 
soil thus obtained upon that part of the road 
nearest to where it is produced, it may often 
have to be conveyed a considerable distance ; 
and, whenever that proves necessary, carting 
the soil in common or three wheel carts, will be 
found more expeditious and cheap, than moving 
it by barrows, notwithstanding that barrows are 
preferable for short distances. The least slope 
that a road called level should have, is a yard 
perpendicular in a mile of length; but, as so 
slight a slope as this will barely affect the water, 
two, three, or even four yards in a mile, will be 
better, and will produce a sensible run or dis- 
charge of the water. A greater slope should be 
avoided if possible; because, when the slope is 
rapid, the water of hard rains runs with such 
velocity and force, as to wash away part of the 
materials that compose the roads or side-banks. 
As to the width of roads, no rule has ever been 
adopted, since they should be made suitable to 
the kind of traffic expected upon them. Asa 
cart or carriage can pass upon a track 8 feet 
wide, and 3 feet more allows a foot passenger, or 
even a horseman to pass, many roads or lanes are 
found that do not exceed 11 or 12 feet in width ; 
but this is a very bad plan, and one that should 
constantly be avoided, unless in deep cutting, 
tunnels, or other positions, in which, from local 
circumstances, such confined width is rendered 
necessary. It precludes the possibility of good 
drainage or repair, and when two carriages meet 
in opposite directions, is productive of serious 
inconveniences, even if occasional wider passing 
places may have been provided. Such narrow 
roads are only made with a view to economy, 
but it is economy of a false kind; for, if the 
wheels of heavily laden carriages are con- 
el 
