The Yakima herald. [volume] (North Yakima, W.T. [Wash.]) 1889-1914, 1911-04-19
Commissioners and Engineer Hard
at Work on Subject of Most
Vital Interest
CALIFORNIA PROCESS
TO BE TRIED BY THEM
This Process Has Evolved What Is
Known as Asphalt Macadam,
Which Expert Says Is Demon
strated Fit for City or Country

The improvement of the roads m
the county is the subject that is near
est the hearts of the county commits
sioners and the county engineer and
they are on the lookout for anything
new in road building that will be Of
benefit to this locality, where the
highways, because of the volcanic ash
soil, are dusty most of the year. Re-
Gently they have been considering a
process that has proven of great value
| in California, where conditions are
somewhat similar to Yakima county,
and the city officials are watching de-
Avslopments along this line for the
purpose Of adopting that which will
offer the best results for North Yak
imas streets. III. r. Postle, of Los
Angeles, speaking of this process, and
of road Improvement generally in
California says
"The California process of road
building has evolved what may be
| designated as an am,
which has, during the past ten years,
demonstrated its fitness for country
roads and all residence streets not
subjected to extraordinary traffic.
| In California Cities
| "The California cities which have
a large mileage of asphalt macadam
streets are Pasadena, Hollywood,
Riverside, Redlands and Ventura.
The city of Los Angeles. profting BY
| the experience of her surrounding
smaller cities, has. during the present
summer laid her nrst asphalt-mac-
adam pavements.
| "The Pacific Electric railway uses,
with very satisfactory results the as
phalt macadam construction between
the car tracks on streets paved will,
sheet asphalt in the city of Pasalen
ana Long Beach. The county Of Los
Angeles has issued bonds for $S,500.-
| 900 and is now building three hun.
dred miles of such roads. San Joa-
quin and San Diego counties have
each sold bonds amounting to ons
and one-half millions of dollars TO,
building county roads. The counties
of Ventura and Santa Barbara are
building many miles of asphalt-mac-
adam rods
Three Methods of Construction
There are three prevailing meth.
DDS of construction. One method 4,
to spread and COMPACT by the steam
roller a layer of foundation macadam
consisting of stone two and one-hali
or three inches in size to thickness
of about four inches when COM
| pacted; this layer of stone is then
coated with LIQUID asphalt at a tenn
perature of about 200 degrees +. al
the rate of three-fourths of a gallon
/ per square yard of surface covered A
| second layer of stone three-fourths OF
an inch to one and one-half inches
in size is then applied and compacted
| to a thickness of about two inches
A second coating or liquid asphalt al
a temperature of aboub 200 degrees
f. is then applied at the rate OF
three-fourths of a gallon per square
yard of surface covered. The surface
| of the roadway is than covered to a
depth of not more than one-half inch
with rock screenings, free from dust
After being thoroughly rolled. third
application of liquid asphalt at a
temperature of 200 degrees F. at the
rate of one-fourth OF a gallon Der
square yard of surface covered, Is
given, lightly covered with screenings.
dampened AMI again rolled. which
completes the work.
"A second method is to plow, pull
verze and crown the roadway. thor
oughly mix into 1t about two gallons
of liquid asphalt for each square yard
and to partially solidify II by tamp-
| ing machine. Al this point from two
to five inches of crushed rock. or
gravel, are added, coated with about
one gallon of liquid asphalt per
square yard of surface covered. SUIT
| ficient material of the road surface Ia
cultivated into the rock to supply a
binder. when the whole is tamred
with tamping machines until it lis
compact and unyielding. The finish
consists of a coat of liquid asphalt