How did Gulf nakhudas (pearling boat captain) produce the routes they traversed around the Indian Ocean? This article draws on the writings of one Kuwaiti nakhuda, Mansur bin Ibrahim Al-Khariji (1879-1954) to explore the intellectual labour that made movement and circulation in the Gulf and Indian Ocean possible. His manuscript, which he produced after a long sailing career, includes notes on navigation, on transactions, and on the political geographies he traversed, together with stanzas of poetry. His notes shed light on the workings of a world in motion – of institutions and ideas that animated circulation around the Gulf and Indian Ocean. Through engagement with Al-Khariji’s writings, this article offers reflections on a nautical world that has been pushed to the margins of a terrestrially moored historiography.