Then the eureka moment. My thumb clamped down on the mysterious lever, I push off from the curb and the scooter seizes on this ounce of momentum. It whirrs into life. I zip to the crossroads and I turn left: now I’m bearing down on Porta al Prato. I try to hug the curb without pranging myself on the parked cars, but most of the overtaking drivers give me a generous berth. It can really go some, this thing: the speedo touches 25 kmph. Thank God the brakes are good. But when I veer left onto viale Belfiore, it’s because I’m getting a new ride, as they say in the heist movies. Before I set off, the app had alerted me to a little squadron of BiC scooters parked right here, positively bursting with juice.