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.
Apalachicola, Florida
In 1849, Apalachicola physician Dr. John Gorrie discovered the cold-air process of refrigeration and patented an ice machine in 1850. He had experimented to find ways to lower the body temperature of fever patients. His patent laid the groundwork for development of modern refrigeration and air conditioning, making Florida and the South more livable year round. The city has a monument to him, and a replica of his ice machine is on display in the John Gorrie Museum. The John Gorrie Memorial Bridge, originally built in 1935 and rebuilt in 1988, carries U.S. 98 across Apalachicola Bay to Eastpoint.