EARTH, SAXD-CLAY, AXD GRAVEL EOADS. 
25 
Middle West, and the average rate of grading with a grading machine 
is, therefore, much less than one-fourth mile of road per day. 
USE OF ELEVATING GKADEK. 
Figure li shows an elevating grader at work. The essential 
features of this machine are a plow with a heavy moldboard, an 
elevating belt, a suitable frame for supporting the plow and belt, and 
driving and adjusting mechanisms for operating the belt and con- 
trolling the work. The plow loosens the material and throws it 
onto the belt, which conveys and deposits it either in the roadbed or 
wagons. 
Elevating graders are adapted especially to building up embank- 
ments with material excavated from shallow borrow ditches along 
Fig. 14. — Elevating grader at work. 
each side of the road. They also may be used to advantage in 
excavating long, shallow, through cuts and loading the material thus 
excavated into wagons for use in building up embankments at other 
points. The latter use, however, is restricted to situations where 
there is sufficient space to operate the grader and at the same time 
afford passageway for the teams and wagons to follow under the 
end of the belt to receive the successive loads as the grader is drawn 
forward. 
It is customary to employ a traction engine for operating the ele- 
vating grader, though teams are used sometimes. Ordinarily, the 
machine may be operated successfully either with a 25-horsepower 
tractor or with 12 well-trained horses. A well-constructed elevating- 
grader, adapted to either horse or tractor power, may be purchased at 
an average price of about $900. 
