Livingstone, David, 1813-1873. Letter to Unknown, 7 April 1857. Images copyright Royal College of Surgeons of England. Images reproduced with kind permission of the President and Council of the Royal College of Surgeons of England. As relevant, copyright Dr. Neil Imray Livingstone Wilson. Creative Commons Attribution-NonCommercial 3.0 Unported (https://creativecommons.org/licenses/by-nc/3.0/). 