Guano mining—tunneling, picking, and blasting the stuff loose and hauling it to waiting ships—was arguably the single worst job you could have in the nineteenth century. It offered all the backbreaking labor and lung damage of coal mining, but to do the job, you had to be marooned on a hot, dry, pestilential, and foul-smelling island for months. Respiratory diseases, causing workers to pass out or cough up blood, were common. So were gastrointestinal ailments—the unsurprising consequence of crowded conditions, rotten food, and a dearth of fresh water.
