The Cairo bulletin., 1909-09-21
| ROADS
AND a.
RoAD N1Ak1Ns.1@sAs>
FOR TAR MACADAM ROADS.
They Reduce TO the Minimum Force
Required to Haul Load.


Required to Haul Load.
The treating and mixing of tai
macadam, says Good Roads Maya
zine, was done by hand in this coun
try until Mr.. Arthur Brown, the city
engineer OF Nottingham. cooperate
ing with Herbert G. Clark, another
engineer, invented an apparatus tC
supersede the crude method OF heat
ing granite chips on an iron slab and
then mixing them with hot tar, Il dis
agreeable process, which has been
found TO produce sundry throat trou-
bles, The new apparatus consists
first of hopper. into which the ma
terial to be treated is delivered d.
rectly from carts or wagons either
by tipping or other suitable methods.
The material is fed into n cylinder
from the hopper by mechanism
which regulates at an even rate the
supply of the material, Stag or other
wise, and delivers Ii into the cylin-
der, which is divided into longitude
nal compartments, and SO inclined
as TO pass through 1t readily the ma
terial delivered into 1t. 1t Is mount
ed on anti-friction rollers TO mini
miZe the driving power Inside this
cylinder Is an inner cylinder or
trough, containing worm conveyor.
Under the apparatus are two com
bustion chambers In which coke fires
are maintained for supplying heat to
the outer cylinder and its longitu-
dinal compartments. and also TO the
outside of the inner cylinder or
trough containing the conveyor.
These combustion chambers supply
that also to two tanks holding the tar
or other mixture, which are situated
at the lower end of the apparatus in
the form OF saddle over the cylin-
der Connected with these tanks are
pipes, which. are coupled to a piece
OF mechanism for automatically dis
tributing or spraying the tar onto
the Stag or other material.
The process Is, therefore, as fol
lows; Stag or other material Is de-
livered into the hopper and fed auto
into the longitudinal peck
cts In the cylinder. AS this cylirder
is inclined, the material is slowly
passed through as it revolvas, is
thoroughly dried and heated and
then falls into the lower end OF the
inner cylinder, where 1t receives the |
proper amount OF tar, and Is turned |
over and mixed in the trough which |
contains the worm eonyeyor, when II |
Is delivered at the upper end thor. |
oughly mixed and coated. The uuan. !
tity OF tar is adjusted TO the speed of |
The feed of the machine. and there |
ran be no surplus or deficiency OF |
tar 1t is claimed that the inventors
have solved the difficulty. never be- |
Tore overcome, Of drying. heating
and mixing the material in one ap-
paratus at one operation, and that
he cost OF the mixing is at most one.
fourth the mixing by hand. The pre-
,ess, from the emptying of the gran.
tie chips into the hopper until they
ire ready to put down on the road,
occupies about four minutes. The
lppartus ia now being manufactured
II this city.
Respecting tarmacadam roads In
General, it Is. claimed that they give
he maximum amount of mud and
lust, and that they reduce to the
minimum the tractive force required
o haul load. A good sample OF
UGH a road is favorite drive along
he river Trent, England, which ap.
ears to be In perfect condition after
We years use. 1t is stated that Bel.
ian engineers sent to this country
y King Leopold to investigate tar
laeadam roads, after visiting sey.
raj places pronounced this the hest
hey had seen; and that the event
al result was the construction Of q
Imilar road from Ostend to Blank
nberg, Belgium, principally for the
Sc of the King in motoring.