Atlanta semi-weekly journal. (Atlanta, Ga.) 1898-1920, 1909-09-21


but still we needed some substance that
would hold together the stone particles
and furnish a surface that would be proof
against the automobile wheel with its
power of sucking up the surface particles.
That substance seems to have been found
in bituminous products.
BITUMINOUS PRODUCTS.
"On this stretch of road" he cont'n-
ned 1--WE are experimenting with three
such products: First, an. artificial oil
asphalt; second, refined coal tar and re-
fined cook oven tar; third, heavy as
phaltic oil"
All these substances. Mr.. Hubbard ex-
nlained. are what we commonly under
stand as crude oil boiled down to a thick
er constituency than the oil itself; reduc-
ed 10 a condition I'm which the volatile ele-
rnents are at a minimum. On the DeKalb
county road they are poured upon layer
of crushed granite and then upon the bi-
luminous stun itself is sprinkled a more
finely crushed covering Of granite. This
ton layer of stone gradually settles into
the bituminous product and thus makes
irm. solidified mass that holds down the
strata OF stone underneath
These lower strata furnish an interest
ing example of the minute labor with
which an up-to-date road is constructed.
veyed and graded. Then the surface Is
dressed to rid it OF unevenness, and the
cutters and curbing are laid. Next
steam roller goes over the soil, packing
II firmly. Thus what is known as the sub
grade is developed At this stage found
alton Of rough. comparatively large
stones are imbedded In the native earth.
Next. what is known as a No. binding
OF crushed stone is put down and rolled.
After this still another covering OF stone
more finely ground than the bottom layer
Is spread. The next process is the binder
itself. Hitherto on most of the roads OF
this section a finely crushed granite
mixed with water has been used as a
binder. But, for reasons explained above.
this has proved insufficient. The blum
nous products being tried on DeKalb
county's roadway furnish one of the hrst
experiments of the kind known to this
section.
Mr.. Hubbard is using about IL gallons
OF the artificial oil asphalt, renned tar
or asphaltic oils to the square yard. The
whole thing is an experiment. he says
but there are known instance OF roads on
which this substance was employed as
binder remaining in splendid condition
for 30 years. WheH asked as 10 the cost
OF such material he saio:
time bindings. but it's durability Is econ
omy in the end. II should not cost more
than is or 20 cents per square yard In
excess of ordinary bindings. Roads have
been built and have stood the test for
two years ard their bituminous binders
have cost no more than this. The great
value of the bituminous substance Is
that Il dries and becomes semi-solid. This
is proof against automobile tires or any
other vehicle.
81 am not yet prepared to say he
continued, (which of these three btu
minious products will prove the most de-
sirable The experiment We are max
ing right here will aid me in doing So l
shall draft a full report in time and
shall furnish the DeKalb county authort-
ties with copy"
Mr.. Hubbard leaves today for Birming-
ham and thence to Washington. II pos
sible, he will return to Atlanta shortly
and it is hoped that he Will spend some
time studying Fulton county roads. He
was brought to DeKalb county through
the influence of County Commissioners
Freeman and W. A. Neal, Jr.
The thoroughness with which DeHalb
has set about improving her roads is a
valuable and stimulating example to the
entire state and section. To begin with,
she invested $4,000 in modern road con-
struction machinery. That seemed a big
outlay, but Commissioner Freeman is
satisfied that II will prove cheap in the
end. By special arrangement with z.
Rivers and the Silver Lake Land COM
pany IL has access to an immense granite
quarry located on that property and from
this Il drills its supply OF material This
year only a few miles OF roads are be-
ing built. but the number will be in
creased from year to year.
The significant fact Is that here is a
county which has turned good roads en-
thusiasm to practical, definite account 1t
is working intelligently with an eye to
the future II is spending brains as well
as money and energy. 1t is going abouf
the work as studiously as a bank does It's
investments. More than this. IL is now
specializing on one particular phase Of
road construction, namely. the binder
problem.
For that reason the work no win pro-
gress on that stretch Of Peachtree road is
of statewide and southwide interest.
Everyone will wait to know what sort Of
road binder DeKalb county chooses. Mr..
Hubbard declared yesterday that still
another problem has arisen IN connec-
ton with that of bituminous binding.
That is the need OF adequate machinery
10 heat and to distribute the product.
At present II is necessary to Fay the pro-
duct by hand, to pour 1t along the road
from buckets.
we must have some device OF distrib-
utinK II more quickly and evenly" he
said. Designs are now being made for
just such machines. however. and I
think we shall have them in the near
future"