Her lifework was a crusade against ignorance and prejudice; as she said, a "diffusion of physiological knowledge would not only tend to prevent disease, but would also be a potent factor in the preservation of morality".

She became imbued with the belief that a physician's most sacred duty is to prevent rather than cure disease, and to that end, she gave many private lectures to her patients.

She commenced first in small towns, with a boy as agent, who engaged churches and wrote with crayon in blank spaces the place and time of the meetings.

In November, 1883, she stood before an audience of 4,500 people in the exhibition building, Sydney, New South Wales, where she was introduced by Charles A. Kahlothen, U.S. Consul.

The proportions of her enterprise may be judged from the fact that her party had been increased to nine people, and it cost her US$450 to rent the chairs necessary to seat that building for five lectures.

[1] In November, 1884, she sailed for London, England, where she delivered her first lecture in the large St James's Hall, on February 17, 1885, where Edwin Atkins Merritt, then U.S. Consul-General, presented her to an audience of 3,500 people.

Before her departure from the U.S., she purchased 20 acres (8.1 ha) of wild land near San Diego, and during her absence, she had it converted into a garden, in the center of which was erected a beautiful house of three stories, costing upwards of US$40,000, an institution that became a public monument to her brother, Dr. Joseph Longshore, who was the most active in obtaining the charter for her alma mater.

The large audience of women rose and greeted her with prolonged cheers, and a committee presented her with an elegant testimonial engrossed on parchment and signed by Caroline Scott Harrison, Eliza Hendricks, May Wright Sewall, Mary Harrison McKee, Governor Alvin Peterson Hovey and many members of the State Senate and House of Representatives, and when she returned there two months later, the common council placed the use of Tomlinson Hall at her disposal without charge.

According to a review in Light (1911):— "It consists of more than 60 brief papers in essay form ranging over many subjects, useful and educative, although at times, a trifle declamatory.

Various passages in the book show that the author is in full sympathy with the great harmonising conception of a life beyond, and she writes with conviction of the soul's eventual entrance into another sphere.