[1] The daughter of William Henry Farthing Johnson, a private school master, and Harriet Brimsley, she was born in Cambridge.
[1] In 1881, she was placed in the equivalent of the First Class of the Natural Sciences Tripos (at that time, as a woman, she was not permitted to earn a degree).
She also published a study on the development of cranial nerves in the newt embryo with Lilian Sheldon, then a student at Newnham College.
[1] In 1890, she became private secretary to Eleanor Mildred Sidgwick, a leading figure in the Society for Psychical Research.
[5] Eleanor Sidgwick became principal for Newnham College in 1892 and Johnson served as her secretary until 1903.