^88 Roads * 
I 
they have the fewest gullies across theni, unless the ground is na- 
turally boggy. 
It would be out of place here to give instances for the con- 
struction of roads in countries which are not sandy and yet per- 
fectly level. I will only remark, that to raise the whole artificial 
part of the road a foot above the common level, to lay it flat across, 
and to effect a very small alternate rise and fall at short distances 
longitudinally would be a mode perfectly efficient — as very ample 
experience has proved. (D) 
In roads however that have a natural inclination to the hori- 
zon, it is difficult to conceive, how the idea of convexity ever ob- 
tained admittance into practice. The makers of roads appear to 
have been more anxious to get rid of rainwater than on any other 
account. It is not pleasant to drive or ride through ponds or pud- 
dles in the public highway : but there need not be any fear, that 
they will abound or exist, if the surface of the road be well and 
equally laid, even if the road were quite flat, provided it were 
raised above the level of the land on each side. But in a road 
which has a longitudinal declivity the only danger is, that the 
water will run off too fast, and carry with it all the small particles 
of hard stone, which filling up the interstices of the larger pieces, 
fix them firmly in their places, and which convexing them in some 
degree diminish the friction of the wheels and preserve the road. 
There cannot possibly be any occasion to turn off these particles 
from the road altogether by a lateral (producing with the longitu- 
dinal declivity an oblique) current of water, and of course an ob- 
lique gully, even if the road could possibly be quite smooth and 
free from tracks and ruts. But as no road, and least of all, a con- 
vex road can be free from ruts, while narrow wheeled waggons 
are used, the convexity of the road becomes useless at least. For 
the water will run from the centre into the first rut that it finds and 
continue to follow it until it finds some vent sideways, accidental 
or artificial. Since then the convexity of the road cannot perform 
the service expected from it, on account of the longitudinal tracks, 
the actual evils it creates ought surely to be avoided. The prin- 
cipal of these is the unequal bearing of the load of carriages upon 
their wheels, thereby wearing the lower side of the road, and 
forcing — by the cutting of leading ruts ; — all the waggons to 
follow the same track, in which track there will be always chuck 
holes* in the lower side, whenever a large stone happens to be 
* In the middle states, chuck holes, are sudden and deep depressions in the 
rut, and are always found opposite to the root of a tree, an old stump, ora 
stone. 
