[May 2, 1921] A feature film is shown with a sound sequence for the first time. D.W. Griffith's "Dream Street" plays in two New York theaters equipped with Photokinema, a sound-on-disc technology. Griffith introduces the movie in a brief sound clip.
from /r/100yearsago
[1921年5月2日] 一部故事片首次以声音序列放映。D.W.格里菲斯的 "梦之街 "在纽约两家配备了Photokinema（一种光盘声音技术）的影院播放。格里菲斯在一个简短的声音片段中介绍了这部电影。