EARTH, SAND-CLAY, AND GRAVEL ROADS. 23 
inches wide. Then make the initial trip with the point of the blade 
cutting about 18 inches outside of the stake line and the outside 
rear wheel of the machine against the face of the furrow. The 
material loosened by the first furrow then will escape under the blade 
in a ridge just inside the stake line. 
(3) Readjust the machine so that when the outside horses follow 
the initial furrow in making the second trip the blade will cut a 
new furrow of somewhat less width than the first and the outside 
rear wheel will follow the face of the new furrow. Then make 
successive trips with the machine adjusted in this way until the 
outside edge of the side ditch is approached, except that after each 
two trips it is well to rest the team by readjusting the blade and 
pushing the loosened material over toward the center of the road. 
For this latter work the blade inay be set at a greater angle with the 
road, and the heel should be lowered and the point raised, so that 
the cutting edge will conform closely to the crown of the road while 
the machine is in operation. 
(4) Repeat the above-described operation, omitting the stakes and 
beginning about 18 inches farther from the center each time, until 
the side ditches are excavated to the required depth and the road is 
approximately to the required cross section. 
(5) Bring the outside faces of the side ditches to a uniform slope 
by making one or two trips of the machine with two wheels, one 
front and one rear, on the bank and the cutting edge of the blade 
against the slope. 
(6) Make several trips over the road, cleaning out the ditches and 
smoothing up the surface. The last few trips should be made with 
the blade reversed, as this method tends to produce a better com- 
pacted surface. But, in any event, it is necessary that during the 
first few months after the grading is completed the road surface 
should be kept smooth while it is being compacted under traffic. To 
do this may require frequent use of the grading machine or the drag. 
Plate II shows a model constructed by the Office of Public Roads 
and Rural Engineering for the purpose of illustrating in small space 
the successive steps involved in grading a road through level county 
by means of a grading machine. 
The method of operating a grading machine described above 
necessarily will have to be modified at times in order to meet special 
conditions. Where, for example, the ditch area is covered with heavy 
sod or contains a number of large roots, it may be very desirable to 
plow this area and cut the roots with an ax before using the grading 
machine. If this is done the plow furrows should be turned toward 
the center of the road and the line of the initial furrows should be 
controlled by two rows of stakes as described above. If the sod is 
