How It's Made Season 29 Episode 6 Fireplace Bellows, Calissons, Diving Watercraft ( Air Date 2017-03-20 ) Genre Documentary category. Overview "Shaped wooden boards are joined by flexible leather chambers and fitted with valves and nozzles to create fireplace bellows. Almonds and candied fruit are ground into a paste, formed over wafers and covered with icing to make calissons, while a streamlined hull, engine, controls and movable fins are combined into a recreational watercraft capable of diving beneath the surface and leaping from the water.".