Diuresis used to increase urine output and decrease extracellular fluid volume. Substances in the circulation can also increase the amount of circulating fluid by increasing the osmolarity of the blood. This has the effect of pulling water from the interstitial space, making more water available in the blood and causing the kidney to compensate by removing it as urine. In hypotension, often colloids are used intravenously to increase circulating volume in themselves, but as they exert a certain amount of osmotic pressure, water is therefore also moved, further increasing circulating volume. As blood pressure increases, the kidney removes the excess fluid
Water organ by the Greeks, the hydraulis continued to be used through antiquity in the Roman world. In the Middle Ages, Eastern Roman (Byzantine) and Muslim inventors developed, among other pieces, an automatic hydraulic organ (described by the Banu Musa in their 9th-century treatise "Book of Ingenious Devices"), a 'musical tree' at the palace of Khalif al-Muqtadir (ruled 908–32), and a long-distance hydraulic organ that could be heard from sixty miles away (described in the Arabic "Sirr al-asrar" and later translated into Latin by Roger Bacon). By the end of the 13th century hydraulic automata had reached Italy and the rest of