Tarmac

Tarmac is a black and gluey composite material. It mainly consists of aggregate which is held together by a viscous tar-like substance, generally bitumen. Tarmac (short for Tarmacadam) owes its name to the process of road construction invented by Scottish engineer John L. McAdam in the 19th century and to the use of tar, later introduced by inventor E.P. Hooley, who patented Tarmac in 1901 as a material for road surfaces and founded a production company bearing the same name. The use of tar in road construction goes back to the beginning of the 19th century, but it was only in the 20th century - when the car market started to flourish - that it became widely used to overcome the problems of dust generation and erosion and wear. As a by-product of the petroleum industry which produced petrol and diesel, the price of tar decreased as car use and the consumption of petrol and diesel increased. For more information see our other sample of tarmac (33) and a blog post about this sticky substance.