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" () 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.
Ctesibius
Ctesibius or Ktesibios or Tesibius (; fl. 285–222 BC) was a Greek inventor and mathematician in Alexandria, Ptolemaic Egypt. He wrote the first treatises on the science of compressed air and its uses in pumps (and even in a kind of cannon). This, in combination with his work on the elasticity of air "On pneumatics", earned him the title of "father of pneumatics." None of his written work has survived, including his "Memorabilia," a compilation of his research that was cited by Athenaeus. Ctesibius' most commonly known invention today is a pipe organ (hydraulis), on which the invention of the piano was later based.