Show DEPTH OF MACADAM tb th Tt Jkr th the books the th greater th abo att t ila 11 the th lod many so 0 o called macadam road roads con of ft a few anchel of broken stone alone laid on the surface of the he L ground without any provision for pre Tenting the tone from lip reading nailer under the pressure of loads there should bo be made a trench ct of the width and depth intended for the roadbed for light six ix inches of tone stone on a good foundation will answer but for heavy thie this is i not sum clesil the pressure of a load passius over a oom compact road spreads out through the body hotly in tc form the apex being at ibe loud load ou on the Bur face NN ith a depth of 0 but 6 0 inched the weight nt at the th bottom vill be spread ont out ever 36 square inabu if it Is i 0 9 inches deep the weight on the foundation will wi 1 spread ter 81 quare square inches and evil it if 13 12 inches deep it mer aquaro square inches depth of roand roadbed bed means the area of tho the bass sustaining ning the weight of the load as a the square of the depth A road 13 12 incle adeep ie is four time times as a strong as a one six auch buchok deep |