Changing Circular Motion to Back-and-Forth Motion

At the Discovery Centre this week, we spent a lot of time experimenting with motors, gears and connectors.

Kind of by accident, I made this machine that translates the “circular motion” of a rotating gear into “back and forth” motion of a rod.

I’ve watched this video I shot over and over and over and it still looks like magic to me. But I’m pretty sure it’s the physical basis upon which my Golding Jobber № 8 letterpress works, so I feel like I should understand more about what’s going on. Physicists?