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Goldsworthy Marlinspike is a descendent of Elias Marlinspike, the founder of Bilgewater. He is a "celestial navigator," with both astronomical and nautical instruments in his cabin. He hopes to guide the three "star galleons" of Bilgewater, together with their human and saurian crew, to the "buckle on the belt of Orion."
A marlinspike is a tool used in ropework for tasks such as unlaying rope for splicing, untying knots, or forming a makeshift handle. (See Wikipedia.org for more information.)