Early Timekeeper’s Stop Clock
Aristo Import Co., New York | The New All American Aristo Football and Basketball Stop Clock No. 135 with Time Out | Ca. 1920s | Metal, glass, plastic
A typical early game included a timekeeper at courtside, who used either a whistle or a starter’s pistol (also used in track meets) to signal the end of a period or game.
This model included a special “time out button” as its newest innovation.
(Black Fives Foundation Archives)
The home team had a distinct advantage in early basketball. 
The timekeeper often literally had the game in his hands. 
This “stop clock” image with a symbolic red light and traffic cop didn’t stop home cooking. 
The game could be sped up (F) or slowed down (S) using a tiny switch on the back of the clock.