Lister’s curiosity had been piqued. Why was it that a majority of the ulcers healed when they were debrided and cleaned with the caustic solution? Although he didn’t dismiss the idea that miasma could be partly to blame, he wasn’t convinced that the foul air was entirely responsible for what was happening on the wards of University College Hospital. Something in the wound itself had to be at fault—not just the air around the patient.
