The deep has long been treated as somehow separate from the surface world, a shadowy non-place populated by alien creatures. While this is partly a response to the difficulty of studying it, it also reflects an ingrained tendency. As the writer Robert Macfarlane has observed, humans are creatures of the air and light, and we have often regarded the spaces beneath our feet with abhorrence, associating them with death, entombment and the unseen and unnameable. And while what Macfarlane calls the underland might be a place of ritual power as well as a place of burial, the ocean’s depths are more frequently equated with loss and forgetting.
Although those versed in traditional wayfinding techniques often understood the ocean in more complex ways, the idea of the deep as an unknowable non-place was also embedded in navigational practices. For European sailors plying the waters of the Mediterranean sea and the Atlantic and Indian oceans, all that really mattered was knowing where potential obstacles and risks such as reefs and sandbars lay – a way of thinking that transformed the ocean’s depths into a blank irrelevance.
