raft (redirected from Ratis)

raft, floating platform of wood, cork, or air-inflated rubber for conveying goods or people. Originally, several logs, bound together by vines, strips of animal skin, and later rope, formed a flat surface upon which goods and people could move across bodies of water. From prehistoric times to the 19th cent. rafting was an important means of transportation. Rafts were indispensable in the frontier period of American history; on rivers such as the Ohio and Mississippi they were used to convey settlers and transport supplies. Large rafts are still used occasionally on the Pacific coast to float lumber along the coastline. In recent times life rafts have come to replace lifeboats on many vessels. Because they are more easily handled and cannot capsize or crash in launching, life rafts can merely be thrown over the side of a ship or permitted to slide down into the water. They contain distress signals and other emergency paraphernalia to sustain the lives of persons awaiting rescue.