The ranch. [volume] (Seattle, Wash.) 1902-1914, 1909-04-01
GOOD ROADS
WIDTH OF WAGON TIRES.

bills have ben introduced in the legis-
lature regarding the width of tires to
be allowed on state and county roads.
Some of these have been killed by in
definite postponement, but others are
to be acted on. One of these provides
a minimum width of three and a max
imum width of six inches.
Several years ago the Missouri Ex-
pertinent Station published the follow
ing:
f.. Numerous tests of the draft of wide
and narrow tired wagons have been
made at this Station during the past
two years, on macadam, gravel and
dirt roads in all conditions, and on
meadows, pastures and plowed fields,
both wet and dry. The draft has been
determined by means of self-recording
dynamometer. The net load was in
every trial the same, viz, 1000 pounds.
Contrary to public expectation, in a
large majority Of cases the draft was
materially less when tires six inches
in width were used than when the tests
were made with tires of standard width
one and one-half inches. A sum-
mary of results follows:
1. On macadam street, as an aver
age of the two trials made, a load of
ISIS pounds could have been hauled
on the broad tires with the same draft
that a load Of 1000 pounds required on
the narrow tires.
2. Gravel roads. In all conditions of
the gravel road, except when wet and
sloppy on top, the draft of the broad
tired wagon was very much less than
that of the narrow-tired wagon. Aver
aging the six trials, a load of 2,4S2
pounds could be hauled on the broad
tires with the same draft required
for a load of 1000 pounds on the nar-
row tires.
g.. Dirt roads. When dry, hard and
free from ruts and dust, $3.50 pounds
could have been hauled on the broad
tires with the same draft required for
1000 pounds on the narrow tires. On
clay road, with mud deep and drying
on top and spOngy underneath, a large
number Of tests showed uniformly ia
vorable to the broad tire. The differ
ence amounted to from So to IS per
cent, or about 5000 pounds could have
been hauled on the broad tires with
the same draft required to draw 1000
pounds on the narrow tires. In this
condition of road the broad tires show
to their greatest advantage. AS the
o dries and becomes firmer, the diff
ference between the draft of the broad
and narrow tires gradually diminishes
until it reaches about rs to 80 per
cent on dry, hard, smooth dirt, gravel
or macadam road, in favor of the broad
tire.
Clay road, surface dry, with deep ruts
cut by the narrow tires in the ordinary
use of the road. In every trial the first
run of the broad tire over the narrow
tire ruts has shown a materially in
creased draft when compared with that
of the narrow tire run in it's own rut.
The second run of the broad tires in
the same track where the rut is not
deep completely eliminated this disad
vantage and showed a lighter draft for
the broad tire than the narrow showed
in the first run.
Where the ruts were eight inches
deep with rigid walls, three runs of
the broad tire in it's own track over
the ruts were required to eliminate the
disadvantage. Three runs of the broad
tire over this track have in all cases
been sufficient, however, to so improve
the road surface that both the broad
and narrow tira6 MO oonC ooeeo5 o,o.