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
Cetacean surfacing behaviour Cetacean surfacing behaviour Cetacean surfacing behaviour or breaching is a group of behaviours demonstrated by the Cetacea infraorder when they come to the water's surface to breathe. Time intervals between surfacing can vary depending on the species, surfacing style or the purpose of the dive, and some species have been known to dive for up to 85 minutes at a time when hunting. In addition to respiration, cetaceans have developed and used surface behaviours for many other functions such as display, feeding and communication. All regularly observed members of the order Cetacea, including whales, dolphins and porpoises, show a range