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.
David Boswell Reid
Prof David Boswell Reid MD FRSE FRCPE (1805 – 5 April 1863) was a British physician, chemist and inventor. Through reports on public hygiene and ventilation projects in public buildings, he made a reputation in the field of sanitation. He has been called the "grandfather of air-conditioning".