Thomas Moore has long been considered Ireland’s national bard and the face of colonial grievance in Ireland. But he also grew up in a port city and then travelled with and worked for the British Navy. Dubbing himself 'transatlantic Tom', Moore rode and wrote about the currents of the north Atlantic and coastal locations key to naval operations and trade routes. Following Moore on these lines of motion allows us to trace local and global circuits, including literary networks, agricultural trade, interests in the Atlantic fishery, migration, military activity and the coercions of the slave trade. Powered by water, such motion pulls against the fictions of stable, bounded property necessary to the British Empire and influential in British Romanticism. Moore not only transits Irish Romanticism and British Romanticism: he is also a window onto a sea-level view of the Romantic era.