Convection (or lack thereof, actually) causes burnt tongues all around the world - in this clip, George Porter explains how it works. Chances are you'll still eat your apple sauce piping hot, but at least now you know why this struggle afflicts us. Watch the full 1976 #XmasLectures on our website. It's free and no registration is required 👉 rigb.org/christmas-lectures/watch/1976/the-natural-history-of-a-sunbeam | Royal Institution of Great Britain