oads. But if the natural soil exhibits peculiar characteristics or is of a distinct type, the road may be referred to by some dist

which may have been shaped and smoothed for traffic or may be in its natu

e and somewhat tough when dry and therefore resist to a degree the tendency of vehicles to grind away the particles and dissipate them in the form of dust. Such soils retain a reasonably smooth trackway in dry weather even when subjected to considerable traffic. Other soils do not possess the inherent tenacity and stability to enable them to res

the various parts of the world. But wide differences are also encountered in the soil on roads very near each other and even on successive st

in the soil is beneficial in that practically every soil compacts more readily when moist than when dry because the moisture aids in binding together the particles. But most soils also

y locality must of necessity be adapted to the climatic conditions, and the amount of work required to give the highest possible degree of serviceability will be exceedingly variable from season to season and from place to place. In regions of great humidity, earth roads may be expected to have a low average of serviceability, while i

tch is particularly preferable to the other and since some engineers prefer the V section and others the trapezoidal section both are shown. It would appear that the V shaped ditch is somewhat the easier to construct with the

ss Section f

Regions of Cons

year unless they are constructed so as to minimize the effect of water. This is done by providing for the best possible drainage and by adopting a method of mai

e grade reduction should be completed, except for minor cuts which can be han

nd of these the most economical cannot be readily determined. Ordinarily a contractor or a county

ng under the end of the apron. When the wagon is loaded, the grader is stopped while the loaded wagon is hauled out and an empty one drawn into position. The motive power for the elevating grader is either a tractor or five or six teams of mules. For many kinds of work, particularly where frequent turning is necessary or where the ground is yielding, mules are preferable to a tractor. The apron is operated by gearing from the rear wheels

ity, suspended from a four-wheel wagon gear. When loading, the scoop is let down and filled in the same manner as a two-wheeled scraper or "wheeler." The pull required to fill a Maney grader is so great that a tractor is ordinarily employed in place of a "sna

can conveniently be loaded into the wheeler and a heavy plow is ordinarily employed for that purpose. Two furrows with the plow will loosen a strip of earth about as wide as the scoop of the scraper a

along the ground. It is drawn by one team and the capacity is two to five cubic feet, but the material spills out to some ex

mules for efficient work. It differs somewhat from the ordinary slip scraper in shape an

Proper Cr

ofile of the location is satisfactory, and the surface is to be shaped to a prescri

d be made passable for vehicles. This requires that clods be broken, weeds and grass that are mixed with the earth be removed by harrowing and forking and that the surface be carefully smoothed with a blade grader. This latter operation will have to be repeated several times before a satisfactory surface is secured. But this miscellaneous work is highly important and under no circumstances ought to be neglected. Nothing so detracts from an otherwise credit

dicapped if there are wet sections along the road, through which the tractor must be driven. In many cases its use

ractor-gra

operator to steer the grader independently of the tractor. Thus the grader can be steered off to the side to cut out the ditches, while the tractor continues to travel on the firm part of the road. Earth moved with the blade grader is usually fairly free from large lumps and can readily be smoothed to a

e or elevating grader work plus a moderate amount of grade reduction in the way of removing slight knolls. For the amount of grade reduction necessary in rolling country, followed by grader shaping, $1000.00 to $1800.00 per mile will be required. The method is not adapted to rolling country where the roads are undulating and

ition of the surface will naturally deteriorate rapidly during the first season it is used unless the road receives the constant maintenance that is a prerequisite to satisfactory servic

. If the work is done while the road is too wet, the first vehicles traveling the road after it has been dragged will make ruts and to a considerable extent offset the good done by the drag. If the road is too dry, the drag will not s

3.-Roa

of loose material left in the middle after the work is completed. Some patrolmen start at one side of the road and gradually work across the road on successive trips, f

erial is moved crosswise of the road and that is the proper method to pursue. In that case no ridge will r

t along the road about twice a year, the ditc

mplished by one man giving his entire time to the work, and t

ds in Ari

erent road problem exists. The effect of precipitation is of significance primarily from the standpoint of erosion, and the

design is adapted to prevention of erosion rather than to elimination of ground water effects, or the softening effects of surface water. Generally the rainy period does

surface into dust to such an extent that an excessive dust layer is produced. In such locati

importance as in humid areas and

oving or preventing accumulations of drifting sand or dust. Crude petroleum oils h

c will continually seek a new track during the period when the road is muddy and is as likely to cross the ditch to the sod near the fence as to use any other part of the road. Continual and persistent maintenance is therefore essential to even reasonable serviceability. At best the earth road will be a poor facility for a considerable period each year in the regions of year-aro