584 The National Geographic Magazine 



First and Second Courses of Wood Covered with Lump Clay 



Pile of Wood and Clay Completed and Firing Begun in One of the Flues 



Burning the Roads, Clarksdale Mississippi.— After the road has been ploughed 

 as deep as a four-horse team can drag the plough, the clay is heaped in furrows 

 and then pieces of wood laid across the ridges. Alternate layers of clay and wood 

 are built on this foundation. Photos from Office of Public Roads. 



