_Case 43_ occurred in Guy’s Hospital, on December 5th, 1854. The patient was a woman whose leg Mr. Birkett was about to amputate on account of malignant ulceration. She gave her age as fifty-six, but appeared ten years older. “In each eye was a fairly marked arcus senilis, but the woman was not known to have suffered any symptoms referable to thoracic disease.... The administration of the anæsthetic was conducted by Mr. Bryant, the inhaler used consisting of a fold of lint, rather larger than an out-spread hand, and protected on its back by a piece of oiled silk to prevent wasteful evaporation.... In the first instance, about a drachm of the fluid was poured upon the lint. The patient inhaled it kindly; and, after about two minutes, another drachm was added. A stage of excitement now followed, during which the limbs required to be held. Insensibility was just fully established, and Mr. Birkett was on the point of commencing the operation, when Mr. Callaway, who was compressing the femoral artery, exclaimed that the pulse had suddenly ceased entirely. The wrist was examined, and the same found to be the case. Almost immediately afterwards, a long-drawn inspiration, attended with a deep sighing noise, was observed. For two or three breaths the cheeks puffed out during expiration; the respiration next fluttered, and then ceased. Mr. Birkett at once put his finger into the patient’s mouth, and drew forward the tongue, artificial respiration being meanwhile commenced by assistants by means of compression of the chest. A few slight inspirations were attempted by the patient subsequent to the commencement of the artificial assistance; but they did not continue, and no sign of vitality was ever afterwards shown.... It must be noted, that the woman had been very pale both before and throughout the exhibition, and that no change in her appearance was perceived when the alarming symptoms occurred, excepting that the superficial veins of the neck and temple became distended with blood. The cessation of the pulse was most sudden. Mr. Callaway stated that it was not preceded by the least premonitory fluttering, the stroke having been good one beat, and entirely wanting the next. This order of symptoms was of course suggestive of death beginning at the heart (cardiac syncope), the cessation of the functions of the nervous system having been markedly subsequent to that of the circulation....