6 
BULLETIN 463, U. S. DEPARTMENT OF AGRICULTURE. 
is not realized that they can not be accomplished except by means of 
a careful survey, and that such surveys can be made only by experi- 
enced men who have been trained especially for such work. Farmers 
and business men generally are inclined to underestimate the amount 
of skill required to make a road survey properly and their influence 
has been responsible in the past for much bungling and for uneco- 
nomical road work for which they have had to pay in heavy taxes. 
Figure 1 illustrates an error which is made sometimes by inexpe- 
rienced persons in grading a road without first having surveyed and 
planned the work. In this figure, which is an actual profile of an ex- 
isting road, line A shows the original ground surface, line B shows 
the grade to which the road was actually constructed, and the dotted 
line (C) shows a grade line which, if it had been followed, not only 
— A shows the original grade of an old road 
r V shows a wrong. though greatly used method of 
cutting the top of the hm and filling in at the bottom 
: The result is no improvement except to shorten 
[the grade 
: "C'shows the proper method of cutting the face of 
==J the hill instead of the top. thereby reducing 
the steepness of the grade without increasing the 
J amount of material moved. 
Fig. 1. 
would have required no additional work, but would have reduced 
the steep grade materially and thereby improved the road con- 
siderably. 
In fitting the grade line to the ground surface and balancing cuts 
and fills it should be borne in mind that earth, after being thoroughly 
compacted, will occupy less space in an embankment or fill than in its 
original position. The customary allowances for shrinkage and 
waste in road work are : 
Per cent. 
For heavy cuts and fills 10 to 15 
For average grading 13 to 20 
For light grading 20 to 30 
For very light grading and considerable sod 30 to 40 
Solid rock will expand from one-third to one-half of its original 
volume when taken from a cut or excavation and placed in an em- 
bankment. But the spaces between the particles of stone should be 
filled with earth as the stone is being placed in the embankment. If 
this is done, no allowance should be made for the increase in volume 
when balancing cuts and fills. 
