to flush the scale
41economic systems — Introduction the way in which humankind has arranged for its material provisioning. One would think that there would be a great variety of such systems, corresponding to the many cultural arrangements that have characterized human society.… …
42Ecotourism — Llano del Muerto waterfall in El Salvador …
43Water purification — This article is about large scale, municipal water purification. For portable/emergency water purification, see portable water purification. For industrial water purification, see deionized water. For distilled water, see distilled water. Water… …
44Megatron — For other uses, see Megatron (disambiguation). Not to be confused with Pegatron. Megatron is a character from the Transformers franchise, created by toy companies Hasbro and Takara. He is the primary antagonist and leader of the evil faction… …
45Acer rubrum — taxobox image caption = Young specimen showing bright red fall foliage status = G5 status system = TNC status ref = Citation | last =NatureServe | contribution = Acer rubrum | title = NatureServe Explorer: An online encyclopedia of life, Version… …
46Orange (fruit) — Orange Orange blossoms and oranges on tree …
47Manhattan Project — This article is about the atomic bomb project. For other uses, see Manhattan Project (disambiguation). Manhattan District The Manhattan Project created the first nuclear bombs. The Trinity test …
48airport — airport1 /air pawrt , pohrt /, n. a tract of land or water with facilities for the landing, takeoff, shelter, supply, and repair of aircraft, esp. one used for receiving or discharging passengers and cargo at regularly scheduled times. [1915 20;… …
49Opera della Luna — Opera della Luna, founded in 1994, is a British touring theatre troupe of actor singers focusing on comic works. Led by artistic director Jeff Clarke, it takes its name from Haydn s operatic setting of Goldoni s farce Il mondo della luna. The… …
50Roman technology — is the engineering practice which supported Roman civilization and made the expansion of Roman commerce and Roman military possible over nearly a thousand years. The Roman Empire had the most advanced set of technology of their time, some of… …
