Omaha daily bee., 1909-01-17

Paris municipality. where wood paving
blocks are cut and prepared and made ex-
cursions to Versailles and Fontainebleau
where studies were made of the construc-
ton and maintenance Of park and forest
roads. Finally the whole congress went by
special train TO Nice for the purpose Of ex-
aiming the mountain roads in the hills to
the northwsrd OF Nice and Monte Carlo
and the seaside highways of the Riviera
where oil and tar have been longest and
most successfully used for the suppression
of dust.
DO Not Dauag Highways,
1T is only possible to m In the
briefest form some Of the more important
conclusions which were reached by this
notable gathering Of experts in road con-
struction and maintenance. Among the
resolutions adopted was one Affirming that
motor vans, draws, delivery wagons and
other vehicles used for commercial pur-
poses cause no serious damage to highways
so long as, first, the average speed is not
more than nine miles an hour and the
maximum speed does not exceed fifteen
miles and the weight on the heaviest axle
does not exceed three tons, with tires of
india rubber, or. second, when the average
speed Is SIX miles an nOuT ana the mdAl-
mum nine miles. the weight on the heaviest
axle when working not exceeding four tons,
the driving axle to have metallic tires with
smooth faces.
The same resolution declares that the
weight on the driving axle should be re-
stricted to three tons and the pressure
on each centimeter of width of the tire
should never exceed $50 kilos-38 pounds.
1t was the opinion of the congress that
properly built roads are not injured by
motor vehicles travelling at any pace not
exceeding fifteen miles an hour, and
there was a general sentiment among the
delegates that before the whole problem
can be satisfactorily solved legislation will
be necessary to compel motor vehicles to
be built with governing devices which will
prevent them from being driven above GER
tain well defined rates of speed.
Keeping Down the Dust.
THE question upon which was concen-
trated the most acute discussion and which
brought out the sharpest diversities of
opinion was the use of coal tar as a sur
facing material for roads to prevent erosion
from rapid traffic, protect the roadway
from infiltration of water and for the
suppression Of lust. On this subject the
delegates were somewhat sharply divided,
with the advocates of properly
applied-somewhat largely in the majority.
ut was maintained by the opponents of
tarred roadways that tarring is only a
temporary and therefore expensive eX-
pedient; that 1t reduces but does not
wholly suppress dust; that the tar is
ground up by the steel shod motor tires,
and being mixed with ordinary dust is
irritating and injurious to the lungs; thai
it kills trees and other vegetation along
roads on which 1t has been used, and that
cattle refuse to eat grass in pastures and
meadows upon which tar-impregnated dust
has settled from the adjacent roadway.
THE advocates of the tarring process
maintained, IN the contrary, that wher
properly applied in warm, dry weather &c
a well built road with a good surface ant
free from flooding and subterranesn in
filtration of water tar forms a cheap ant
excellent protective service which not onl,
minimizes the wear of traffic upon tn,
roadway, but practically suppresses mus
and dust. 1t is mot denied, however, tina
on heavily travelled ~thoroughfares the onl,
really satisfactory method of application
is by mixing the crushed rock or other sur
facing material with tar or asphalt to tn