When the alarm is first rung at the box, whether by crank or automatically, a signal is sent to a Central Fire Alarm Station. When a box is activated, a coded wheel starts to spin in its interior. This wheel had notches etched into it that, when the wheel begins to turn, run against a stationary finger. When the notches knock against the finger, the electrical signal created by the rotating wheel is interrupted, and at the central station, a mark is placed on a moving piece of tape. The number of notches corresponds to the box number. For example, box #267 located at Market and Beale would produce a code as follows: -- ------ -------. Each alarm went through to the central station four times.
     Once a station received the alarm indicating that station would have to respond to a fire, the operator rang a bell to signal the firefighters. As the alarm began to ring, the lights were automatically turned on and the magnetic latches holding the horses’ stalls closed were released. This, along with a loud, piercing alarm, informed the firefighters of the fire and where it was. Before the era of radios, firefighters had to not only stay close to the fire station at all times, but also had to live near to the fire station. Firemen either lived at the fire station in bunks or lived within the surrounding block so that every fireman was able to respond to every fire alarm.