The Mankato free press. [volume] (Mankato, Blue Earth County, Minn.) 1879-1924, 1902-01-10
A NEW ROAD MATERIAL.

Charles Rollin Reyes. calls attention
of burnt clay as material for the
building of good roads. Burnt clay,
or as. it is more widely known,
"burnt gumbo" has been extensively
used in the west, he says, for years
for railroad ballast and has proved to
be first class material for that pur-
pose, and so satisfactory is it, that it
has been used where good rock lodges
abound. AS this burnt gumbo appears
for Railroad ballast he says sit is a
red, gravelly material, in which the
fragments are sharply angular Tin
shape, very porous. and very hard.
On the WHO'S it is not unlike coal Gin
ders in appearance, except that the
color is red. This material is prepared
and delivered ready for use for rail
road purposes on board cars at cost
of from % to 30 cents cubic yard.
And he says that when burnt by hand
as it would have to be for highway
purposes, it would cost about 10, or .15
cents per cubic yard more. But in the
matter of highway use, it can be, he
says, prepared right on the spot, .and
only needs shoveling ouJ.and .back
again where the clay can be obtained.
For matchmaking purposes..on
county roads, Mr.. Reyes, states. that
burnt clay is not quite as durable : as
some.of the best grades of rock, but
possesses advantages to Offset this, :. in
that 1t requires practically no capital
for its preparation as --the "most ordi-
nary labor and little common sense
on the part of one person, as overseen,
can produce the best results. AS to
preparation he says that the "road
should be properly graded and crowned
before putting on the gumbo road
metal. A surface of burnt clay, six
to eight inches in thickness, is COM
monty sufficient for good results or
ten inches in particular places, where
unusual conditions exist or traffic is
especially heavy" He further claims
that with no more expense and effort
than is now put on country roads to
keep them in good repair, they can be
gradually covered with burnt clay so
that within dozen years system of
highways equal to any of those for
which France has so long been noted,
could be produced A burnt clay road,
he says, is never muddy, for that pro-
perty was lost in burning, but is hard
and smooth and is practically free
from dust after the highway system
has been we'll developed so that mud
is not brought on to it from tributary
roads. 4..
AS to the process of burning he says:
"Along the roadside cord wood is
piled to form low pyramid or ridge
eight to ten feet wide. On this three
or four inches of coal slack and from
10 to 90 inches of gumbo mud, which
is cut from the roadway, or a pitt as
the case may be. On firing the wood,
enough air enters the pile to enable
slow combustion to be carried on with
out the generation of too much heat,
which would vitrify the clay" The
more sticky the clay is, the more
water it holds, the better its
quality for road material after the
burning process and it can be taken
out of low wet places where it is filed
with water. The very best test of
gumbo mud for this purpose, he says,
is to find the very worst stretch of
muddy highway in the country.
Here is a solution for road improve
ment, if clay of the right quality can
be obtained here. Perhaps if it is not
of exactly the same quality as that
to by the writer in the Re-
view of Reviews it might make quite
a durable road material, and put our
country roads in far better shape and
for far less money than can be done
in any other way. 1t is matter that
would be we'll worth looking up at
least, and some little experimenting
done to test its value with our soils