How did the wooden pegs on an Egyptian lock key open the bolt?

In an ancient Egyptian lock, the wooden bolt is secured by an assembly of vertical pins that drop into holes on the bolt's upper surface, effectively locking it in place. The key is a large wooden bar featuring upright pegs that correspond to the arrangement of these pins and holes.

To open the lock, the key is inserted into a keyhole located beneath the vertical pins. When the key is lifted, its pegs push the pins upward, clearing them from the holes in the bolt. Once the pins are raised, the bolt is free to be slid back, allowing the door to be opened.1