The item below is a receipt for interest from the Minehead Turnpike Trust from December 1859.
The Turnpikes were necessary to support Mail and Stage coaches, providing a reasonable road surface (rather than roads that were 100 yards wide with travellers trying to find a bit that was not boggy or rutted). The McAdam road surfaces (after John McAdam) consisted of a layer of medium sized stone with a layer of smaller stone on top, filled in with stone dust. The key thing was that the size of the top stones was smaller than the width of the coach tyres.
When cars started going along faster they sucked up the stone dust and destroyed the roads, so a layer of tar was applied to the top - hence Tarmacadam or tarmac. Current roads apply the top layer as a mixture of stone and tar (rather than spraying tar on top).
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