Join us in the penultimate episode of our first season as we talk about lenses, kettles, eels, and lighthouses. For our main topic, we discuss the optics of the human eye and how we see colour and in the (almost) dark. We also discuss different disorders of the eye and certain why people need glasses. Before then, we discuss what exactly causes the whistle of a tea kettle and how electric eels are able produce their powerful shocks. Finally, Liam tells us the story of Augustin-Jean Fresnel (He apologizes for his consistent mispronunciation of the name.) and his invention that has saved countless lives: the Fresnel lens.