During my senior year in high school, I owned a 1929 Model A Ford. Due to their primitive distributor, they tended to fire the spark plugs at the wrong time. To deal with this, there was a spark advance/retard lever on the steering column. If you retarded the spark while coasting, the engine would backfire.
It also had a throttle lever on the steering column. This was used when starting it with a hand crank. Retard the spark, set the throttle at 1/4 and crank away. Retarding the spark kept the engine from fireing before top dead center and having the crank break your arm when the engine tried to run backwards.