In the mid-1800s, before general anesthesia, St Thomas’ Hospital used the attic of a neighboring church as a space where surgeries, mostly amputations and other quick-hit procedures, could be conducted where students could watch but other patients couldn’t hear the agonized screams. When the hospital moved in 1862, it was abandoned, sealed away, and forgotten. It was considered lost until 1956, when an enterprising historian thought to look in the attic, and found the secret surgical stadium behind a wall. Creep up a tight wooden spiral staircase once used by the bell ringer and you’ll find the theater, now the centerpiece of a ghoulish, but carefully educational, museum delving into medical methods of the early 1800s, from herbal remedies to leeches. On a recent visit, a 7-year-old boy in a visiting school group nearly passed out during a mock bloodletting showand-tell; the staff, accustomed to fainters, casually produced a pillow and a glass of water without halting the demonstration, proving that in the old days, medicine was less about science and more about soldiering on. Which you must also do; there are no toilets here.