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.
Arthur Frederick Ostrander
Arthur Frederick Ostrander, Sr. (February 14, 1895 – February 1978), was an assistant scientist. He worked with inventor George Poe. In his childhood he worked with Poe (mid-1907 to 1908), who taught him how an artificial respiration device functions. His assistance to Poe was instrumental in the successful development of the respiration device, as he performed the fine detail work and metal fabrication that Poe could no longer do. His face came to be one of the most well known of the time, having been featured in several large circulation newspapers."