Scientific Road-Making 101 



of six, seven, or eight feet ; these prevent the water from 

 falling into the side drains ; they also throw a considerable 

 shade upon the road, and are gross and unpardonable nui- 

 sances. The materials, instead of being cleaned of the mud and 

 soil with which they are mixed in their native state, are laid 

 promiscuously upon the road." 



In planning new roads Telford cut right through the hills, 

 wherever possible, in order to avoid unduly steep gradients. 

 In making the roads he first arranged a solid foundation of 

 pieces of durable stone, from 4 in. to 7 in. in size, these being 

 carefully put into position by hand, with the broadest side 

 downward, and packed with small stones in between. On the 

 rough pavement thus formed he laid an upper course of small 

 broken stones, with a binding of one inch of gravel. Between 

 the two courses a drain was set across the road every hundred 

 yards, Telford attaching great importance to the carrying 

 off of all water that might percolate through the upper course 

 on to the lower. He gave a uniform and only moderately 

 convex shape to the surface of the road, abandoning, in this 

 respect, the ideas of his more amateur predecessors. But his 

 system was one that called for much labour and care, as well 

 as for an abundant supply of the needful materials, and the 

 cost of carrying it out was proportionately high, if not, in 

 some situations, prohibitive. 



McAdam preferred to be considered a road-repairer rather 

 than a road-builder, and his methods differed materially from 

 those of Telford. He became, also, much more of a propa- 

 gandist in the work of road-improvement, enforcing his 

 theories with such success that he brought a new word into 

 the English language, roads made or mended according to 

 the main principles he laid down having been known ever 

 since his day as " macadamised." 



Born in Ayrshire in 1756 one year before Telford McAdam 

 went to America at the age of 14 to start life in the counting- 

 house of his uncle in New York. Subsequently he became 

 a successful merchant, and returned in 1783 to Scotland, 

 where he bought the estate of Sauchrie, and then, in 1785, 

 began to devote his attention to road-making, which was to 

 occupy his thoughts and absorb his energies for the rest of 

 his days. Roads he came to regard as, in his own words, 

 " perhaps the most important branch of our domestic 



