Physician
After studying in Europe, Hall returned to the United States, where she was appointed physician to the State Reformatory for Women in Sherborn, Massachusetts by Massachusetts Governor Thomas Talbot. Connected with the prison was a hospital of 150 beds, likely to be filled from a body of from 300-400 inmates. Clara Barton, who succeeded Eliza Mosher as superintendent of the hospital at the reformatory, praised Hall's leadership in the hospital.
"Four years later, it became my privilege, as superintendent of that prison, to observe how that duty was discharged by its resident physician. Perfect system prevailed. No prisoner could enter upon her term without a careful diagnosis of her physical condition and administration of the needful treatment. If any trace of mental trouble manifested itself, the case was closely watched and tenderly cared for. The most difficult surgical operations were performed, not only without loss of life but with marked success. The control of the doctor over her patients, and these included from time to time nearly every inmate, was simply marvelous, and her influence throughout the entire institution not less remarkable. Among all classes, she moved as one born to command, that most successful of all command, the secret of which lies in tact, conscious ability and sympathy with mankind. So long as that prison remains a success, so long will the influence of Dr. Hall's early administration and example for good be felt there.
After nearly five years of service at the reformatory hospital, she was appointed superintendent by the governor and his council, though she declined the position, as its acceptance would necessitate the giving up of her medical work.
Soon after that, Hall formed a partnership with her colleague, Dr. Mosher, and together they began to practice in the city of Brooklyn, New York. In the autumn of 1884, they were appointed associate professors of physiology and hygiene and physicians at Vassar College, resigning in 1887. The same year, upon the occasion of the semicentennial commencement of the University of Michigan, Hall, as first Vice President of the Department of Medicine and Surgery, was called upon to preside at the meeting of that body. As her colleagues, many of the most eminent physicians and professors of the land were present. Afterward one of them remarked: "I had predicted that fifty years after the admission of women, a scene like this might occur. My prophecy has been anticipated by more than thirty years."
In the fall of 1887, Hall was appointed central committee delegate to the fourth International Conference of the Red Cross, of Geneva, held in Karlsruhe, Germany. She was invited as a guest at the court of Frederick I, Grand Duke of Baden, and Princess Louise of Prussia. That conference brought Hall into contact with many noted people of the European courts, where she was reportedly admired widely. At the end of Hall's visit, Princess Louise gave her various gifts as tokens of remembrance. Her standing in medical jurisprudence was recognized by the courts of justice in New York and she was often, called as an expert by the Supreme Court to take charge of examinations instituted by that tribunal.
After moving to Los Angeles, California, she made a visit to Japan, where she visited hospitals, schools, missions, prisons and police courts. On leaving the country, she was urged by Japanese officials of medical and public education to return and lecture on physiology and hygiene. She returned to Japan for several months in 1907, lecturing in various institutions. In a letter to a Brooklyn friend, quoted in the Brooklyn Eagle, she wrote:—
"To-morrow I go to Yokohama, to talk to a girls' club, foreign this time. I shall feel queerly to find myself talking to any girls not Japanese. I am to go to Kobe soon, and to Kyoto, and one other place not far away, and I am meeting a great many people, both native and foreign. A few days ago a gentleman, his uniform all a-glitter with orders, drove up and sent in his card. Baron Dr. Ishigaro; I met him just twenty years ago at a Red Cross conference, at Carlsruhe. He is now a very great man, and was lately decorated anew by the Emperor. He is a member of parliament. He begged to be allowed to do anything possible for me while I remain in Japan. A number of titled people have called, and I have visited them. It has been of interest to see this side of Japanese high life, and I have enjoyed it very much, but after all the real pleasure has been in getting a hold of these bright-eyed, hungrybrained, vivid and determined young Japanese women, and, more than all these, they are the ones who will give" this sturdy and brilliant nation the final touches needed to bring them up to a full realization of the ideals for which they are reaching and struggling. High and low, I love these people more every day. They are kind, cheerful, glad to serve you for the smallest favor with a sturdy, honest pride."