Evening capital journal. (Salem, Or.) 1888-1893, 1891-05-19
PROGRESS SPEAKS.
Salem on Macadam Answerpd-The
Street Improvement Question
Again Discussed.

EDITOR STATESMAN: There is n
sample of the Polk county rock
Macadam on the crossing of State |
street in front of the bank of Ladd |
81 Bush, not much used, but enough |
to show the wUrthliness of the rock |
for any kind of street pavement Itl
weuld pulverize to dust in a single
year. Give us well graded, drained
and guttered streets, cover, d with
the gravel that lies almost at our
doors, and we will have the best
roads in Oregon, which with little
repair will last half a century.
"SALEM.n
Statesman, May II, 1891.
The "Macadam" referred to above
consists of few handstull of broken
stone thrown loosely on the street
where wheels passing over and
through it have caused it to grind
itself just as diamond will cut dia-
mond. This is no more Macadam
than is loose pile of basalt blocks
Belgian pavement. Macadam is
formed by layers of stone cubes Of
nearly uniform size thoroughly
rolled until they bind and hold
firmly in place, forming a smooth,
bard surface from curb to curb.
Nothing less than a ten ton roller
will do the work well. If the cubes
are not rolled until they bind firmly
ana immOvabIy, but are left in
places loose, so as to move among
| themselves they will grind each
other TO powder whatever material
be used. No fine screenings or sand
whatever must be used except to fill
the interstices of the top course and
hen only after it has been thor
oughly rolled TO smooth surface and
binds solidly together from curb to
curb. This is Macadam, and when
resting on good foundation, well
drained will make good roadway
aud will not "pulyerize to dust''
under ordinary traffic, or under
heavy traffic if it is carried on broad
tires, which act as rollers, while
narrow tires under heavy loads
haye about the same effect on the
road as would disc harrow.
1t is not possible to make good
gravel road where there Is much
traffic. If no soil is used to bind
them, the gravel spheres will move
freely among themselves making q
heavy and disagreeabe road for driv'
ing. If sufficient soil or sand and
clay be used to bed the gravel it will
make pleasant driveway for light
traffic, except when too wet, when
it will become muddy just in proper.
zion to the amount of the traffic
and when too dry will become dusty
and rough with only ordinary use
The authorities agree that the best
stone from which Macadam can bS
made is fine grained syenite or d
basalt of similar quality. They are
better than granite, gneiss, sand
stone, quartz rock, or flint, some o
which are harder, but more brittle
and difficult to break into the proper
cubical shape, and are not so gooC
as either syenite or basalt.
The exhaustive report of compe
tant civil engineer as to the quality
of the basalt referred to above
based upon actual and severe tests
shows that we have in that rock
first-cIass materi al for either Macad
am or Belgian pavement and 1 have
no doubt the basalt boulder which
surround us and from which all our
gravel has been manufactured by
the floods of ages, is better road
metal than that used on 80 per cent
of the best Macadamized roads
in the world. PROGRESS.
Salem, May 10, 1891.