Fisher's father was both an astronomer, at the Royal Observatory, Greenwich, and a priest.

Before leaving home she wrote two novels, Too Bright to Last, 1873, and a three-volume His Queen, which was published in 1875.

[1] Fisher made occasional visits to her mentor, Florence Nightingale.

She was charged with transforming nursing and medical care at the deteriorated institution, where she instituted dramatic improvement in standards of care, and created the hospital's nursing school.

She died of heart disease in 1888, only 13 years after starting training, but had been very productive; her obituary in the British Medical Journal said that during her time at PGH "an impetus was given to the improvement of nursing which has been felt almost throughout the United States".