The setting for this daguerreotype is the teaching amphitheater of Boston's Massachusetts General Hospital. Dr. John Collins Warren, cofounder of the hospital and professor of anatomy, stands with his hands upon the patient's thigh, explaining the proceedings to a student audience seated out of camera range. Dr. Solomon Davis Townsend, who performed the operation, stands behind Warren with his left arm akimbo. An unidentified anesthetist holds a sponge soaked in ether near the head of the patient who, curiously enough, still wears his socks. Warren had commissioned Albert Sands Southworth and Josiah Johnson Hawes to make the first photographic record of an actual live medical operation, which was also the retiring Dr. Warren's last lecture. The doctors' heads all moved during the long exposure, causing blurring and confirming the photograph's candid circumstances.