Letter, 20 January 1860
Letter, 27 July 1875
Letter, 8 May 1878
Letter, 19 May 1879
Letter, 5 May 1879
Letter, 12 October 1880
Letter to William Osler, December 27, 1894
Letter, 13 May 1895
Letter to Harvey Cushing, June 4, 1925
Letter to Harvey Cushing, June 4, 1925
Letter to Harvey Cushing, May 12, 1926
Letter to Harvey Cushing, May 12, 1926