East Oregonian : E.O. (Pendleton, OR) 1888-current, 1905-05-17

ton and 1t is a recognized fact that
there is no investment road builder
can make that will bring the returns
a roller will
After roads have been thoroughly
graded up and well rolled, then comes
the problem of covering them with
some kind of permanent material
Experience has proven that where
rock is available, there is nothing
better when properly crushed and
properly put down. This necessitates
the use Of rock c"Isher, of which
there are hundreds of different styles
and sizes made, yet there are but few
made that can be economically used
by counties for macadamizing pur-
poses.
Qualifications OF Rock Crusher.
| A rock crusher for county use
should he mounted on trucks so it
can be easily transported to various
districts. 1t must be light enough in
weight so that the average county
bridge will easily hold 1t up and yet
1t must be of a sufficient opening in
the jaws and of ample capacity to
economically crush rock. Too many
counties in this country have made
the mistake of buying a crusher too
small in capacity and too small a re-
ceiving opening in the jaws, simply
because they could buy them for a
few hundred dollars less than larger
machine would have cost them, and
the results have been that it has cost
them too much to crush the rock,
and in many districts this has had a
tendency to discourage crushed rock
roads.
1t takes more men to operate ma
chine with a receiving opening of SIX
II inches and with a capacity of 12
tons per hour than it does to operate
crusher with a receiving opening
of 10x1S inches, with a capacity of
80 tons per hour, for the reason that
the receiving openings in the jaws are
so small that it takes from two to
three additional men with hammers,
breaking the rock into sizes that will
allow it to enter the jaws.
All crushers for macadam work
should be equipped with an elevator
and a revolving screen that, will make
at least three different grades of rock
that will pass through the rings of
y or Il and pinch sizes.
Bins are also a very economical and
necessary adjunct to a crushing plant.
These bins can be built of various ca
pacities of three compartments, and
as the rock passes through the
crusher, 1t is elevated up into the re-
volving screen which is situated on
| top of the bins and makes the various
separations. In the sides or bottom of
these bins slide doors and spouts can
be easily arranged so a wagon can
drive under them and be loaded in
two or three minutes with any size
rock desired.
Utility Of Gravel.
In many sections of the country
rock for crushing purposes is not
always available, but there is ample
gravel, and while gravel will not
make as good permanent road as
crushed rock will, it makes a far
better road than dirt, when properly
put down, but to get the best results
from gravel roads, it is absolutely
necessary that the gravel be screened
and separated in various sizes, and
for this work a gravel elevator and
screen has been made. One end of
the elevator is set in the gravel pit
having a large hopper, over which
teams with scrapers can be driven and
the gravel rapidly dumped into the
elevator, which is taken up into the
revolving screen similar to the one
described on the crusher and the
various separations made, and I be-
| lieve it has been thoroughly demon
strated that gravel roads built with
gravel that has been thoroughly
screened is 100 per cent better than
where the gravel has not been screen
ed. These gravel elevators and
screens can be operated by a small
gasoline or steam engine.