Wind chime Japanese glass wind bells known as "fūrin" () have been produced since the Edo period, and those at Mizusawa Station are one of the 100 Soundscapes of Japan. Wind chimes are thought to be good luck in parts of Asia and are used in Feng Shui. Wind chimes started to become modernized around 1100 B.C. after the Chinese began to cast bells. A bell without a clapper, called a "yong-zhong", was crafted by skilled metal artisans and primarily used in religious ceremonies. Afterwards, the Chinese created the "feng-ling", which is similar to today's modern wind bell. Feng-lings were hung from
Wind gradient wind is similar to the geostrophic wind but also includes centrifugal force (or centripetal acceleration). Wind direction is usually expressed in terms of the direction from which it originates. For example, a "northerly" wind blows from the north to the south. Weather vanes pivot to indicate the direction of the wind. At airports, windsocks indicate wind direction, and can also be used to estimate wind speed by the angle of hang. Wind speed is measured by anemometers, most commonly using rotating cups or propellers. When a high measurement frequency is needed (such as in research applications), wind can be