The Abbeville press and banner. [volume] (Abbeville, S.C.) 1869-1924, 1902-11-05
GOVERNMENT RoAoMAKlNe.

GOVERNMENT RoAoMAKlNe.
wsrk Il Construction suppiensntsa ~
Lectures by an Export
Several weeks ago the department Of
agriculture began its first experiment
in roadbuilding at New Brunswick.
n. J., under the direction Of e. B.
Harrison, special agent Of the Office Of
poad inquiry.
The model road being considered is
the first Of several which the govern.
ment 10 to build at the various expert
mept stations throughout tho country.
The government furnishes q rock crush.
or, screen, engine to drive steam roller,
spreading wagon and road grading ma
chine and two skilled operators. The
city furnishes the material, carts and
laborera
The road will be Of macadam pattern.
An inferior grade Of traprock 10 found
in abundance near New Brunswick and
this 10 being used in the substructure
Of the road The superstructure II OBJ
tained from the traprock deposits in
the neighborhood Of Plainfeld and the
Oranges.
The model pavement will have .
depth Of about nine inches and the foun-
dation be made Of small, wedge shaped,
broken stones Of as nearly the same d.
mensions a. possible. The roadbed will
be prepared BY thoroughly rolling with
. steam roller weighing about ten tons.
Every hole will bs carefully filed with
the same material that composes the
rest of the roadbed, and the finished
cross section will be formed by two
grades Of one foot in 80 feet from the
sides, uniting at the center, with the
apex slightly rounded. Four inches Of
crushed stone will be spread on the
carefully prepared roadbed to form the
foundation of the substructure. The
largest Of these stones will be crushed
90 fine as to be able to easily pass
through Q two inch ring, and the smali-
est will be shout half an inch in diam
eter.
This foundation will then be sprin-
kled, making The stone as wet rs posi-
BILE without softening the roadbed, and
the roller passed over it few times
until the stone is only slightly disturbed
by the teams returning with the empty
carts. The first foundation is not made
deeper than four inches, because IL has
been found that greater thickness
causes the stones to "elbow" together,
wearing OF their sharp corners, making
the "bonding. " which is the great de-
sideratum. o very slow process, II not
an impossibility.
When the first foundation has been
thoroughly sprinkled, second coat OF
similar stone three inches In thickness
will bs applied. After the stone has
been well bonded" to this extent 1t will
again be sprinkled. and while very wet
O thin coating If traprcck screenings
will be most carefully spread over the
surface, Just thick enough to I'LL the
small spaces between the stones The
size Of the stones Of this last applica-
ton, which Is called in the parlance OF
.oadbuilding the binder" will be
from half an inch in diameter TO the
finest dust. When the work has reached
this stage, it viii be left untouched In
tho dry state as long as practicable to
harden and bind. The application OF
water and the passage Of vehicles viii
be prevented as long as practicable.
As the work progresses Mr.. Z. B.
Harrison, who IL directing the work for
the department Of agriculture, will de-
liver lectures explaining ths process oi
laying the road. Rutgers college str-
dents In the agricultural department
and fsrmers will be invited to attend
the lectures and witness the work.