FARM DEVELOPMENT 



mined only after the grade has been nearly finished. 

 Materials uncovered while excavating cuts, or materials 

 found in outside areas from which earth is secured in 

 constructing the grade, are often best to use alone or in 

 combination with materials brought from outside in 

 making up the road surface. 



In some instances it is best to give the contractor, and 

 the superintendent (representing the public) who daily 

 inspects the work, some latitude, stating the specifica- 

 tions for the construction of a road surface of a given 

 quality and character in general, yet binding, terms. 



In giving the contract for the formation of the grade 

 or substructure, it can be specified that the best mate- 

 rials for subsurfacing found within the cuts be spread 

 on top of the substructure as a foundation upon which 

 the surfacing materials are to be laid. Thus, by using 

 gravel from cuts, such a well-drained solid top can be 

 put on the substructure that the superstructure need 

 not be made so thick nor so expensive as if such poor 

 materials as soft clay were left at the top, or if the upper 

 part of the substructure were made up of alternating 

 patches of soft clay, coarse gravel, sand, or sand and 

 clay mixed, giving a foundation variable in rigidity and 

 uneven in its capacity for removing water from the super- 

 structure or for allowing surface water to percolate 

 through it. 



Where the surface is- to be made of macadam, brick 

 or other hard substance, and something is known of the 

 availability of sand or gravel desired as foundation under 

 these surfacing materials, the specifications are easily 

 written. 



