The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1892-03-04
THE IDEAL ROAD.

The first prize oHelou w Inc Un1ver-
sity Of Pennsylvania for the best essay
IN on road construction and maintenance
was won bv Engineer Henry Irwin.
The Chicago Herald thus condenses it:
First, as to location and construction.
In tbe older states, where few new roads
are reopired. Mr.. Irwin thinks the ques-
tion Of location would generally become
one IF alteration and alignment, when
hills SIRE met with, rather than of com
nleta new location. In locating high
w p in hilly country it will generally
ba fonnd advantageous to follow along
water courses. and the advantage Of
having the road run close to quarries
from which good road metal may be OBJ
tanned should also be kept in view.
AS TO grades, the steepest grades that
sbould be allowed on public road is
one in twelve. and the length of such
steen hill should not be more than 100
| feet. in order that a horse may not be
overworked before reaching the top with
a heavy load.
A grade one in fifteen may be permit
ted for about 200 feet in length, but
should be avoided. A long stretch of
perfectly level road should also be
avoided, if possible, as surface water re-
o1ires fall of at least one in 100, or
one inch in ten feet.
Drainage is one of the most important
items in road1naking. 1t is almost impos-
sible to make good road on wet, yield
ing soil, except at the expense of hay
ing concrete foundation. Money spent
in securing good, firm, dry roadbed
will save a vast amount of trouble in
attempting to maintain a good surface
and to keep it clean. All roads should
have a ditch OF drain about four feet
deep on each side.
Culverts to carry the drainage across
the road should, if possible, be made of
stone, as timber does not last long and
the caving in of wooden culverts is a
common cause of accidents. In all cases
they should be made larger than sufi-
Gent to discharge the greatest known or
! estimated quantity Of water which has
to pass through them, and their slope
should not bio less than one in 100.
Small culverts up toabout feet inches
square may be builtof dry stone.
Across all level lands the crown of the
road should be raised at least one foot
above the surface of the ground. And
in country roads, where extreme econ
o1ny may be necessary, the central part
of the roadway may be macadamized
for width of only eight feet, and the
entire roadway may be less than twenty
feet, wide. On roads for considerable
traffic the macadamized portion should
be sixteen feet wide, thus leaving space
enough for vehicles to pass without al
ways going into the same track and
wearing the roadway into ruts.
When bank has to be made Of soft
clay it is we'll to lay two inch planks
over the roadbed before placing the
stone on it, as the clay can then CONSOLE
date before the wood rots away suffi
GENTLY to let the stones get out of level.
The slopes of all cuttings or banks
should be sown with grass seed to pre-
vent their being washed away by rain
or damaged by frost. The roadbed
when brought to the required grade
should be rolled several times and
roller of not less than ten tons in weight
should be used. If gravel is used the
gravel should first be screened so as to
remove all stones of more than ~
inches in diameter; the remainder
should be screened again to remove all
earthly matter and the small gravel
which may be less than three quarters
| of an inch in diameter.
The gravel should be put on in layers,
the bottom layer four or five inches thick
and well rolled, and the next layer three
or four inches, also well rolled. If a
roller is not obtainable the first layer
should be allowed to remain till packed
together by traffic before the second
layer is spread. When ruts appear they
should be Immediately filed in, and
traffic directed over all parts of the road
by putting logs or large stones on the
parts most Travelled over till the whole
surface becomes consolidated.
Under the head of maintenance Of
roads Mr.. Irwin treats at length of
ssC1eaning the roadbed," Repairing
the surface" and "Cleaning out the
drains or water courses at the cages OF
the roadway" On macadamized roads,
where. horse machines are not used,
hand machines, such as are used in Eu-
rope, sre most economical. These
scrapers are used by two men and are
about five feet wide. Two men with a
scraper can clean more road surface
than four men with hoes, as the action
Of the machine is continuous. 1t is not
well to clean macadamized road too
closely or to sweep it too clean either of
mud or dust, as the stones may get loose
on the surface.
On the country roads, when repaired,
no road scrapings should be put on the
new stone, as it will prevent it from
binding and become yielding, uneven
surface. The best time to apply the
stone is during wet weather in the spring
and fall. The cleaning out of drains
and water tables should be done in the
spring before the spring thaw sets in,
and in the fall all weeds and grass in
the bitches should be cut and the Gull
| ,,-,-4, ,,,a d;+ohos left in o,ood c],o,,o For.