American surgeon (1817–1887) who performed numerous operations that had never been attempted, including severing the femoral artery to cure elephantiasis arabrum, the removal of an entire lower jaw due to bone necrosis, and the first successful neurosurgery for trigeminal neuralgia. ALS signed “J. M. Carnochan,” one page, lightly-lined, 6.25 x 8, August 10, 1861. Letter of introduction to noted obstetrician James Young Simpson. In full: “Allow me to introduce a young friend of mine, who visits Scotland for the purpose of consulting you in relation to his wife. Mr. James Lorimer Graham, who is the bearer of this, is one of our most respectable and esteemed citizens, and I will highly appreciate your attention to them.” In fine condition, with intersecting folds, one vertical fold passing through a single letter of the signature, and a few spots of scattered toning. Graham was a notable collector of eclectic curiosities, who accumulated many coins, autographs, books, and drawings throughout his lifetime. Simpson was a well-regarded Scottish doctor, known for his advocacy of midwifery and developed the use of chloroform as an anesthetic. A letter associating three fascinating 19th century notables. RR Auction COA.