When people get on the train and it’s quiet, it’s never really that warm either. So nobody opens a window. But when the train gets busy, that beast starts to heat up quick. The people who got on later notice first that the train is heating up. But they’re either standing or in the aisle seats so they can’t reach the windows. And the passengers who are close enough to open a window, they’ve been caught up in reading the Metro or an awful Asda-bought novel. They’re slow to notice that the train is warm. And when they do, they don’t know what has caused it. We sweat because of their stupidity.