The Maryville times. (Maryville, Tenn.) 1884-1944, 1890-11-19
ROAD.MAKiNG.
Some Practical Hints on q Very Impur.
tant SubjeIt.


tant subject.
The following extracts from The En-.
cheering and Building Records prize
essay on road making (by S. c. Thomp.
son, New York;, contain many valu.
able facts:
A man can walk up slope Of 100 in
100, and horse or mule can ascend an
incline OF 100 in 175, and it has been
found by experiment that horse pull
ing his maximum load on level can
pull but four-fifths as much II the slope
is made in 30, and this gradually
lessons until with slope of in 10 he
can draw but one-fourth as mach as his
level load. The maximum grade es-
tablished by the French Government
board Of engineers is in 20. The Holy
head road in Wales uses in 20 as .
maximum, except in two cases. The
road over the Simplon Pass averages
leg on Italian side, and to II on Swiss
side, with one case of to ~, and in this
State several turnpike roads are limited
by law to in II. In laying out road,
with regard to grades, have contiuu-
GUS inclination in one direction and do
not allow any counter grades, for, in as.
cending, each foot descended on coun.
ter grade means just so much more riae
to be overcome.
Where the roadway is too wide it usual
ly results in no part being kept in coed
repair, while if it was narrowed the
whole could be kept in first-class condi-
ton at less expense, and well-kept
road of even twenty feet width is far
preferable to road but half maintainsd
of double the width. In laying cut ii
may be advisable to take strip con.
siderably wider than the intended ,oad'
bed, so as to provide for possible con-
tingencies in the future when the land
becomes more valuable. Lay out sufi.
GENTLY wide, but build only so much as
can be kept in thorough repair. The
essential requirements of good road
bed are that it shall be practically un.
yielding-smooth ON the surface, and
impervious to water-and without these
requirements there can be but little
durability.
For surface draining, bitches should
be provided along each side of the rcat
having sufficient fall to promptly carr,
away any water that reaches them
Where it becomes necessary toearry thu
water across the roadway, culvert
should be provided. All drains SHOULD
have continuous fall throughout theil
entire length, and the size will depen'
upon the inclination and the amount o
water they are expected to carry. Il
portions of the country where gravel |
easily obtained very satisfactory roa'
can be made by making the surface fo
ia greater or less depth Of gravel.
Prepare the foundation 80 as to ALLOW
4 for prompt drainage, and shape as tn,
4 finished road is intended to be; max
the side OF the road planes, and no
curves, and then roll thoroughly to &c
a solid foundation. Put on layer o
gravel from six inches to eight inche
in thickness, sprinkle thoroughly an
roll until very compact and firm. Mex
spread another layer from four to sil
inches OF gravel, and sprinkle and rca
until the desired hardness and smooth
ness are obtained. If the gravel has q
binding material in lit, sufficier
amount may be incorporated in the Las
layer to cause it to take good bond.
Where 1t is possible to get blue grave
or hard pan and clean bank gravel, tn
two can be so mixed as to give surfac
almost like concrete in hardness. Whe
the two are used together two-horI
grooved collier for the first layer will b
found very effective, and the materia
should be quite wet while rolling. Tn
surface can then be finished with
steam roller, or with a smooth role
sufficiently loaded to give the requisit
weight In completing the surface of
gravel or other road, where rolling
required, the weight of the roller shout,
be as mach per inch as the weight pc
inch on the tire of the heaviest vehicl
likely to pass over it. For ordinar
traffic very durable and economies
surface can be thus produced.