| Show HOW DRAGS MAINTAIN ROADS Simple and Inexpensive Device Well Adapted for Producing Smooth and Uniform Surface Prepared by the the- United States Department Department Depart Depart- ment of Agriculture The The- drag Is a simple and Inexpensive inexpensive sive device for maintaining certain types of roads which when wet become rutted under traffic and which become firm on drying out It Is also well adapted for producing a smooth and uniform surface on newly constructed roads In fn which the material used for surfacing Is earth erth earthy gravel or ors orsome s some same me similar material It Is essentially essential essential- ly Iy a maintenance Implement and Its use In fn construction Is distinctly sec sec- Roads which are very rocky or very sandy cannot be materially Improved improved improved im Im- im- im proved by Its use Properly used at the right time the road drag performs four distinct of of- flees First by moving at an angle to the traveled way It ft tends to produce or preserve a crowned cross section Second Sec See ond If used when the material of the surface Is not compact and hard It tends to reduce ruts and other Irregularities irregularities In fn the road by moving material from points which are relatively high highto to those which are relatively low Third when used after a rain it accelerates accelerates ac accelerates ac- ac the drying out of the road by spreading out puddles of water and thus Increasing the surfaces exposed to evaporation Fourth If the surface material Is In a slightly plastic state dr dragging smears over and partially seals the so-called so pores which naturally naturally nat nat- occur In earthy material and thus makes the road surface more or orl orless orless l less ss Impervious to water The advantage advantage tage of this smearing action of the drag will be more readily understood If a sample of ordinary earth Is examined examined ex ex- ex under a magnifying glass Such an examination will show that the earth closely resembles a sponge or honeycomb In structure and the desirability desirability de de- de of closing the open pores will be readily apparent If used Improperly or at nt the wrong time the drag may do actual Injury to toa toa toa a road Dragging a very dry road for example serves to Increase the quantity quantity quan quan- tI of dust and may do additional fy Drag Is 1 Essentially Maintenance Im Im- damage by destroying the seal produced produced pro pro- during previous dragging If on the other hand the road Is very wet and muddy the Irregularities In the surface are likely to be Increased rather than diminished by dragging |
