above three inches thick in most places, and in none more than four: yet on removing the road it was found, that no water had penetrated, nor had the frost affected it during all the late winter; and the natural earth beneath the road was found perfectly dry.
Several new roads have been constructed an this principle within the last three years. Part of the great north road from London by Hoddesdon in Hertfordshire—two pieces of road on Durdham Down, and at Rownham Ferry, near Bristol—with several private roads, in the eastern part of Sussex.
None of those roads exceed six inches in thickness, and although that on the great north road is subjected to a very heavy traffic, (being only fifteen miles distant from London) it has not given way, nor was it affected by the late severe winter; when the roads between that and London became impassable, by breaking up to the bottom, and the mails and other coaches were obliged to reach London by circuitous routes. It is worthy of observation, that these bad roads cost more money per mile for their annual repair, than the original making of this useful new road.
Improvement of roads, upon the principle I have endeavoured to explain, has been rapidly
