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.
Cramerton, North Carolina
Cramer is credited with designing and equipping "about one-third of the new cotton mills in the South" between 1895 and 1915, and simultaneously acquiring extensive holdings in textile mills. Among Cramer's numerous industrial engineering patents was one for the "Cramer System of Air Conditioning", which included the automatic regulation of temperature and humidity. These early innovations in air conditioning resulted more from the need to remove lint from the air (a persistent problem in the textile mills) than to cool the factory atmosphere. The term "air conditioning" is attributed to Cramer.