What Becomes of the Dust?
The dust of the roadway is generally blown away by the wind, to come down to earth again wherever the wind happens to carry it—on the lawns, the doorsteps or back to the road, perhaps. In any event, the rain which is certain to come sooner or later, washes this dust back into the soil, or into the sewers. Part of it mixes with the soil. The organic matter in dust helps to fertilize the soil, and is therefore useful. Other parts of the dust are oxidized and consumed by the air, through the heat of the sun. So you see the dust is continually changing from one thing to another.