The Birmingham age-herald. [volume] (Birmingham, Ala.) 1902-1950, 1909-10-16
ALABAMA EXPERTS
TALK ABOUT ROADS
Professor Kay Discusses the
Use of ebert
MlTCHAM ON METHODS
Prouty Gives Interesting Summary of
Road Building Materials Found
in Alabama and Where
They Are Located.
MlTCHAM ON METHODS

liable read before the Alabama GOOD
Roads association, were presented yester-
day by Alabamas leading technical stu
dents, Edward B. Kay, chief of the de-
partment of engineering at the Univer-
! sity of Alabama; G. N. Mitcham, OF
the Alabama Polytechnic institute. and
DR.. w. F. Prouty, chief assistant of the
state geological survey
These papers give the modern thought
on road building and contain practically
the results of all Alabama's experiments.
/ 1t is the remedy of the family physi-
! clan. That of Mr.. Kay deals with ebert
roads, Mr.. Mitcham tells of the meth
! DDS of road building, and Dr. Prouty
] handles road materials. They are given
here in full:
{ Following is the address of Edgar B.
Kay, dean, department of engineering
of the University of Alabama:
/ The purpose of this paper is to call
attention to a road material found In
inexhaustible quantities within the Dor
ders of Alabama and to show from what
has been done what may be done with
this material, which Mr.. Sam Lancaster
says seems to have been prepared in
natures laboratory especially for road
building"
ebert as a Road Building Material.
ebert is found In the lower carbonif-
erous formation and in the Knox dol
omite of the silurian. In the former
It is generally in more or less regular
beds or sheets; in the latter usually in
the form of concretionary masses. There
are extensive ebert quarries or banks
in Alabama near Florence, FIT. Payne,
Birmingham, Leeds, Bessemer, Admission,
Jacksonville and near other cities and
towns In the Birmingham district 1T
is found everything the red sandstone,
which forms the covering for the Dig
vein of red hematite ore and under
lying the observation-disclosures limestone.
The ebert of the sub-carboniferous for
nation contains between the cleavage
Joints. a proportion of clay and iron OK
ide and although the bank ebert is some
times comparatively soft until 1t is spread
on the ground, it generally makes bet
ter roadway than the hard material.
The ebert from the siurian formation
is harder and more expensive TO quarry
and does not make as good road material
as that from the upper formation. All
the cherts of the state are easily quar-
ried, however, by blasting and the Jumps
reduced to proper size by crushing, nap
ping hammers or by rolling.
ebert is one of the hardest of rocks
but it does not usually occur In con-
siderable quantities in its original beds.
but is generally mixed with more or less
sandstone or limestone, so that beds
! OF pure ebert often grade impercepubly
| into pure limestone or pure sandstone.
1t has splintery or conchoidal fracture
and in color ranges from pure white to
black neutral gray brown, yellow or
! red While ebert varies greatly in quality
and appearance in Its natural beds upon
exposure it becomes hard and tough, Of
ferng a strong resistance to abrasion.
The Alabama cherts contain clay and
iron oxide between the cleavage joints.
are easily and cheaply quarried, do not
require crushing, bind together readily
and make cheap roads that wear well
and are smoother than roads built en-
tirely of limestone. Judged by the quail
tiles required of an ideal road, we find
this material to satisfy as many essen
tial conditions IL not more than any
other material that is extensively used
in road building
1t is low in first cost, as 1t is easily
mined. The total cost on board cars
at pits in the Birmingham district, does
not exceed % cents per cubic yard.
Tt requires no preparation. except
breaking up of the larger masses which
is usually done by rolling or mapping
hammers.
It is more durable than any form OF
dirt or macadam road.
1t produces road surface that is
smooth of considerable elasticity, but
hard enough to have a low tractive re-
sistancy.
A ebert road does not rut when prop
erly built under any condition of traffic
An examination of the highways in JEFF
ferson county, Alabama, which have
been built Of ebert, and were construct
ed over 20 years ago, and many OF them
subject to heavy traffic, will show that
these roads are smooth and in good con-
dition, although they have had practically
no repairs.
ebert does not Produce a slippery road
surface and it affords a good foothod
| over which to draw heavy loads.
| 1t can be used on any grade and does
not wash when thoroughly compacted
, to any greater extent than the best
macadam roads.
| 1t makes a comparatively noiseless road
and yields neither dust nor mud.
! 1t makes an impervious roadbed, and
being smooth, drains rapidly.
| OF light color, it does not absorb heat
| excessively. The color of the surface is
| pleasing and does not produce glare.
| Where the material is plentiful, and
where a good quality Of bank gravel or
Stag is available for q binder it is not
| necessary to go to the trouble and ex-
| pense of cutting out subgrade. 1t is,
| however, essential that the surface course
| contains a sufficient quantity of good
binding material otherwise the bond
/ will soon be broken, the material will
| spread. and much of it will eventually
be forced into the side bitches.
Method of Construction.
| Mr. M. c. Eldridge, chief of records
| United States office of public roads, says
THE roadbed should be shaped with a
| road machine before the material is
| placed and given a slight crown OF from
three-eighths to one-half inch to the foot
i from the center to the sides. The foun-
| dalton should then be rolled, the material
| for the first course spread in two layers
and rolled and sprlnkled in the usual
| manner. The spreading of the material
| can be accomplished by the use Of a road
machine. provided the gravel is not toe
| large. The total depth may vary from
| four to nine inches at the center as sol
| and traffic may require, and gradually
| diminish in thickness TO what is common
| ly called a feather edge II the most ap-
| proved method is followed, shoulders
should be provided to hold the
material in place. The material should
then be spread to uniform depth from
the center to the sides"
The Madison county, Tennessee, roads
| were built as follows: The ebert for the
| Madison county roads was obtained ir
| Alexander county, Illinois. Solid founda-
| tions were first obtained by rolling. First
In thickness. The rolling was from the
| o~l hn nd nnl ro<