One of the most significant advances in bowling was the invention of the automatic pin-setting device, which eliminated boys’ services and dramatically accelerated the game.
When you are in the run-up zone, the magic mechanism is closed by a scoreboard that shows the following information: strike, first or second ball, foul and the number of pins remaining standing. The only piece of equipment visible to the player is the cleaner, which removes the knocked-down pins from the lane, and the setting table, which is lowered onto it to grab the remaining pins in order to clean the lane or install a new set of pins.
The pictures on the previous two pages, with the scoreboards removed, show how the machine, equipped with two sets of pins, proceeds step by step to remove the pins remaining after the first ball and install a new set of pins for the next player who will send his first ball. … The removed cover helps to see the internal structure and to follow the operation of the machine, which removes standing pins and sets a new set of figures after sending the second ball.