The commonwealth. (Scotland Neck, N.C.) 1896-1929, 1908-05-21
AUTOMOBILES AGAIN
Directors Of Office of Public Roads
Conduct Some Experiments.
MOTORS AT A MILE A MINUTE.
Rubber Tired Vehicles Moving at High
Speed Strip and Ruin Roads.
(Cor. to The Commonwealth

Sor. 20 Inc Commonwealth
Washington, D. c.
A two ton racing automobile NOV
ing at something in excess Of a mile
a minute, while an impenetrable
cloud Of fog-grey rock dust hung to
the horizon and marked the speeding
course Of the big machine, was the
sight witnessed by the travellers on
the famous conduit road a dozen
miles from Washington on Thurs
day, April %.
The seemingly pronouced violation
of the speed ordinances was counten-
anced by two of the Nations feder-
al departments; Agriculture and
War; however. the rushing motor
car having been pressed into requisi-
ton by l.. w. Page, Director of the
Office of Public Roads, and DR.. AL
lerton S. Cusham, Assistant Direc-
tor, in the effort to determine the
effects of automobile traffic upon
macadam highways, and the stretch
Of thorougfare was placed at their
disposal by War Department Off
cials.
While the racing car and others of
various weights and types made
many trips over the selected stretch
of mile and half at varying rates
Of speed, from to 65 miles an hour,
a corps Of skilled photographers,
equipped with the most modern de-
vices for photographing vehicles at
very high speeds, made accurate re-
cords Of the various tests.
1t has long been known to high
way engineers that automobiles were
rapidly shortening the lives of the
rock surface roads Of the world, and
many experiments have been made
in the past six or seven years to de-
termine the actual cause of the dam
age done. To understand how the
soft broad tires Of the modern motor
car can work an injury to surface
that not only wristbands, but i'm
proves under the constant passing
and repassing of vehicles with iron
tires, one must be apprised briefly
of the theory on which, first
Tresauget of Limoges, and later
MacAdam of Ayr, worked when
giving such highways to the world.
They reasoned that a road surfaced
with bits of stone would improve
under wagon traffic because the iron
tires of the passing vehicles would
constantly crush the stones and form
rock dust particles; that those rock
dust particles would not merely fill
in all the interstices between the
stones but would also form surface
dust binder; the wettings and roll
ings tending to cement the dust into
shell-like surface and thus make
the entire road one traffic-withstand-
ing, understanding mass.
They reasoned we'll and wisely.
The macadam roads lived up to the
theories of their inventors and i'm
proved with the passing years until
the advent of the automobile. 1t
was but short time after it came
into vogue that highway engineers
in all civilized lands learned that a
new condition was confronting them
and that established customs were
being menaced. The trouble was
quickly traced to the automobile and
it was studied. 1t was soon noted
that the soft rubber tire was the
highway menace. 1t crushed no
rock itself and therefore contributed
no quota of the needful surface dust
binder, while the tremendous trac-
tive force Of the rear wheels drew
up the dust made by the iron tired
wagons and sent it whirling away
over adjacent lands.
Those who witnessed the expert
ments of Thursday near the Nation
al Capital could not doubt for a
moment that the various road eX-
perts all over the world are correct
in the opinion that very rapidly
driven automobiles are rapidly tear
ing up the surface Of the macadam
road, for not only were huge clouds
of dust lifted into the air and blown
off the road, but careful examina-
ton showed that the material under
the wheel tracks of the machine was
distinctly loosened and ravelled even
during the short period of these
tests.
No such effects were noticeable
after the passing of iron tired We
hicles; the series of tests beginning
with the passing of a horse drawn
vehicle. This was photographed as
it moved along and also as the wagon
tires passed a given mark. Then the
automobiles were sent over the
course. The first was a heavy weight