"They think the sea a true medow": calenture of the brain

Calenture's once-famous symptom of hallucinated pastures at sea, perhaps first attested in Kenelm Digby's poorly datable manuscript Loose Fantasies, entered the medical literature in a 1648 work by James Cooke (1614-1694). The eventually canonized case being sailors drowning at night for puzzling reasons, descriptions remained few and contested, not least because febrile and afebrile variants were alleged. At least three seventeenth-century authors (Henry Stubbes, John Moyle, and William Oliver) explicitly construed calenture as a distemper of the animal spirits, formalizing its preexistent vernacular sense of madness. A heavily romanticized relic of humoral pathology suspended for centuries between etiologic ambition and literary appropriation, the illness intrigues not least in terms of the various attempts at both reanimation and reclassification seen especially during the early nineteenth century. The topic especially resonated in francophone medicine, resuscitated as it was in the chronicling of the 1816 Méduse frigate shipwreck, most notably by the ship's surviving surgeon, Jean-Baptiste-Henri Savigny (1793-1843). At the same time, calenture became enmeshed with a number of emergent and established medical constructs, each with a similarly noted appeal to the humanities: delirium tremens, (scorbutic) nostalgia, and heatstroke.