Plague doctor, 1656, uncredited. "A primitive gas mask in the shape of a bird’s beak. It was believed that the plague was spread by birds and that by dressing in a bird-like mask, the wearer could draw the plague away from the patient and onto the garment. The mask also included red glass eyepieces, which were thought to make the wearer impervious to evil. The beak was often filled with strongly aromatic herbs and spices to overpower the miasmas or “bad air” thought to carry the plague.