Tarmacadam Tarmacadam Tarmacadam is a road surfacing material made by combining macadam surfaces, tar, and sand, patented by Welsh inventor Edgar Purnell Hooley in 1902. The terms "tarmacadam" and tarmac are also used, with varying degrees of correctness, for a variety of other materials, including tar-grouted macadam, bituminous surface treatments, and modern asphalt concrete. The term is also often used to describe airport aprons (also referred to as "ramps"), taxiways, and runways regardless of the surface. Pioneered by Scottish engineer in the 1820s, macadam roads are prone to rutting and generating dust. Methods to stabilize macadam surfaces with tar date back
History of road transport the trusts and restrictions on the width of wheels - narrow wheels were said to cause a disproportionate amount of damage to the road. The quality of early turnpike roads was varied. Although turnpiking did result in some improvement to each highway, the technologies used to deal with geological features, drainage, and the effects of weather, were all in their infancy. Road construction improved slowly, initially through the efforts of individual surveyors such as John Metcalf in Yorkshire in the 1760s. British turnpike builders began to realise the importance of selecting clean stones for surfacing, and excluding vegetable material and