The most feared sea monster in history is named after a crooked tree. This episode traces the Kraken from the Norwegian word krake, a makeshift grapnel anchor of spruce branches and stone that came up from the deep draped in seaweed, through synonyms like horven and krabbe that all describe a dragging, many-limbed shape. Written accounts followed in 1646 and 1729, and Olaus Magnus drew a horned beast with flaming eyes on his 1539 Carta Marina, claiming eyes 16 to 20 feet in circumference. Bishop Erik Pontoppidan's 1753 natural history of Norway popularized the island-sized creature whose dive created a ship-swallowing vortex.

The legend then entered science, with Linnaeus including a version in early editions of Systema Naturae and French malacologist Pierre Denys de Montfort classifying a colossal octopus and a Kraken octopod in 1801, blam ...