Science and technology of the Tang dynasty
The inventor Ding Huan (fl. 180 AD) of the Han dynasty invented a rotary fan for air conditioning, with seven wheels 3 m (10 ft) in diameter and manually powered. In 747, Emperor Xuanzong had a "Cool Hall" built in the imperial palace, which the "Tang Yulin" (唐語林) describes as having water-powered fan wheels for air conditioning as well as rising jet streams of water from fountains. During the subsequent Song dynasty, written sources mentioned the air conditioning rotary fan as even more widely used.
Elie Aghnides
Elie Prodromou Aghnides (1901–1988) was a Greek engineer and inventor, most famous for his invention of the faucet aerator. He was born in Istanbul, Turkey, in 1901. He had three siblings: Nicholas Prodromou Aghnides (1883-1979), a former professor at Columbia University; Thanassis Prodromou Aghnides (1889-1984), a former Greek ambassador and undersecretary to the United Nations in London during World War II; and Esmeralda Aghnides (1895-1992). Aghnides was educated in England and received an engineering degree from the University of Belgium.