She was initially educated by her aunt, Frances C. Shepard, and later attended the Rye Seminary, where she met her lifelong friend, Henrietta C.
[3][5] In 1917, she supervised the Club's move to its new headquarters at 47 East 60th Street, New York, and directed the installation of its collections in the new building.
[3] At its new location, Granniss reportedly worked to make the library more open, inviting "non-members, including women and outside scholars" to use the reading room.
[1] Over her career, she authored over twenty books and articles, and organized several exhibitions and their corresponding catalogues for the Club.
She was in frequent correspondence with other scholars and librarians, and gave regular lectures on various aspects of book history.
(Mildred Abraham suggests that this reticence may be due in part to facial scarring from injuries sustained in the streetcar accident in 1917.
)[3][1] Despite her position and contributions, she was barred from membership in the Grolier Club (which remained a male-only organization until 1976), and was unable to attend most of its events.