The fonds contains original and typescript letters, manuscript notes, newspaper clippings, journal extracts, reminiscences and more, assembled by Harvey Cushing chiefly between 1920 and 1924 during the course of his research for the biography of William Osler. For the biography, Cushing collected and retyped over 7500 pieces of Osler's correspondence, among which are some original letters.

The fonds is separated into three series: Manuscripts, Working Notes and Osler's Correspondence. It also contains photographs, annual reports, publications, clippings, one watercolor painting, one postcard. Osler's correspondence is further arranged in three subseries based chronologically.

Letter to Grace Revere Osler from Harold Feil, 609, Osborn Building, Cleveland, Ohio, USA. Feil praises Cushing's "Life of Sir William Osler." He regrets that he never knew Osler. Feil attended Osler's funeral in 1919 with Dr. E.J. Wood.

Letter to Grace Revere Osler from William Turrell, Cherwell Lodge, Oxford, Oxfordshire, England. Turrell thanks Lady Osler for sending him a copy of "Life of Sir William Osler." He feels that the most striking example of Osler's work is the greatly enhanced standard of Medicine in Oxford. He writes of Izaak Walton Jr. Includes partial letter from Arnold Muirhead.

Letter to Grace Revere Osler from P.S. Allen, Corpus Christi College, Oxford, Oxfordshire, England. Allen thanks Lady Osler for sending him a copy of Cushing's "Life of Sir William Osler." Osler's life has been an inspiration to him.

Letter to Grace Revere Osler from Esther Carling, Berks and Bucks Joint Sanatorium, Peppard Common, Oxford, Oxfordshire, England. Carling compliments Cushing's "Life of Sir William Osler" and comments on Osler's "radiant" personality.

Letter to Grace Revere Osler from Rudyard Kipling, Bateman's, Burwash, Sussex, England. Kipling is glad to know that Grace found Revere's grave properly tended to. He comments on the need to honour and remember those who die in war.