Wind it Up! (谷の仕掛けアミを上げろ！, Tani no Shikake Ami o Ageru!, lit. Raise the Valley's Device Net!) is an event from Tomba! 2: The Evil Swine Return. This is the first event involving cogs. This event is obligatory to progress in the game.
When walking all the way to the right in Town of the Fishermen, you'll come to an intersection. Talk to the fisherman to active the event. He'll state that the Star-Shaped Cog is missing, which is obligatory in order to go to Waterfall of Heavens.
To get some clues about where the cog is, you can go to the House at the Point, home of Ark, the fisherman, but this is not necessary if you already know where it is. If you talk to Ark, he will mention that he last saw it when he was by the drying net.
Go all the way back to Kainen's house where a Fish Drying Net is hanging. The cog is hanging in the net. Go and fetch it and go all the way back to Ark's house to activate a cutscene. The event is now cleared and you have access to the Waterfall of Heavens.