irrigation pipe
81American Indians — American Indians † Catholic Encyclopedia ► American Indians GENERAL When Columbus landed on the island of San Salvador in 1492 he was welcomed by a brown skinned people whose physical appearance confirmed him in his opinion that… …
82Sri Lanka — Ceylon redirects here. For the time period of 1948 1972, see Dominion of Ceylon. For other uses, see Ceylon (disambiguation). Democratic Socialist Republic of Sri Lanka ශ්රී ලංකා ප්රජාතාන්ත්රික සමාජවාදී ජනරජය (Sinhala) இலங்கை சனநாயக சமத்துவ… …
83Pipeline transport — An elevated section of the Alaska Pipeline …
84Watermill — This article is about a type of structure. For other locational uses see Milldam . For details of the technologies, see Water wheel and Mill machinery . A watermill is a structure that uses a water wheel or turbine to drive a mechanical process… …
85Wrench — For other uses, see Wrench (disambiguation). A set of chrome vanadium metric wrenches, open at one end, box/ring at the other. This type is commonly known as a combination wrench. A wrench or spanner is a tool used to provide grip and mechanical… …
86List of National Monuments of the United States — The United States has 101 protected areas known as national monuments. The President of the United States can establish a national monument by executive order, and the United States Congress can by legislation. The Antiquities Act of 1906… …
87Tunnel — This article is about underground passages. For other uses, see Tunnel (disambiguation). Underground tunnel for heatpipes between Rigshospitalet and Amagerværket in Denmark …
88Ocean thermal energy conversion — Temperature differences between the surface and 1000m depth in the oceans Ocean Thermal Energy Conversion (OTEC) uses the difference between cooler deep and warmer shallow or surface ocean waters to run a heat engine and produce useful work,… …
89Wastewater — For the lake in Northwestern England, see Wastwater. Public infrastructure …
90Al-Andalus — This article is about the historical region. For the modern day region, see Andalusia. For the district in Kuwait, see Kuwait City. For the musical group, see Andalus. History of Al Andalus 711–1492 711–732 Musl …
