This dissertation studies three pearl fisheries in the northern Indian Ocean – the Persian Gulf, the Gulf of Mannar, and the Mergui Archipelago – at the height of the global pearl boom in the late nineteenth and early twentieth centuries. Based on archives in the Emirates, India, Myanmar, Sri Lanka, and the United Kingdom, this project employs a comparative and connected methodology across the three sites, all of which came under the British Empire. By combining methods from environmental history, the history of science, and labour history, this dissertation aims to write a history below the water line. An eclectic combination of sources, including scientific diagrams, local poetry, oyster specimens, and undersea maps, allows new stories of submarine environments, animals, and marine extraction at the turn of the twentieth century to emerge.

By the 1930s, the industry in natural pearls was eclipsed by the trade in ‘cultured pearls.’ Instead of reading the last fifty years of natural pearling as a period of decline, I argue that it was an important juncture in attempts to domesticate marine creatures and construct the ocean as a site of value. Until this point in time, the shallow continental shelf at sea (where oysters lived) was largely invisible in cartography, science, and law. What does it mean to see like a state at sea? Using the concepts of visibility and translation, I argue that the precise configuration of science, statecraft, and increasing global revenues to be derived from pearls led to new attempts to render submarine space into a source of value. I show here how the seafloor was a space of potential value which required the embodied labour of pearl divers to translate across medium, terrain, species, language, and culture to bring the pearl-oyster bearing reef into focus.

Despite this, attempts to domesticate both labourers and oysters at sea in the early twentieth century were largely unsuccessful. The dynamic, changing nature of seafloor ecologies and materials eluded the grasp of the tools of state visibility. It was only once the oyster was brought onto land, stripped of the terrain of the ocean, that domestication was partly completed.