Prince was a friend to Harry Houdini and Hereward Carrington and they all had exposed the tricks of fraudulent mediums, however, unlike Houdini both Carrington and Prince believed some mediums were genuine. According to the psychical researcher Robert Ashby, "Prince remained highly skeptical of PK and other physical phenomena, but felt that there was no doubt at all of telepathy, clairvoyance and precognition." By 1925 due to the investigation of Mina Crandon the American Society for Psychical Research (ASPR) had been taken over by a spiritualist faction. The ASPR championed Crandon and suppressed any reports unfavorable to her. Prince was alarmed at the number of "credulous spiritualists" that joined the ASPR. In response, Prince who was the Society's research officer resigned to establish the Boston Society for Psychical Research. Prince was accused by supporters of Crandon of being biased against paranormal phenomena. In 1927, Prince contributed to the book The Case For And Against Psychical Belief (1927) which contains essays by both believers and skeptics of psychical phenomena. In 1934, Prince described the Crandon case as "the most ingenious, persistent, and fantastic complex of fraud in the history of psychic research."
Prince had exposed the medium Maria Silbert. She had developed the ability to maneuver a stiletto using only her feet and was thus able to write names on cigarette cases when they were held under the table.Prince attended a series of séance sittings with Rudi Schneider and no paranormal phenomena was observed. In his notes in the Bulletin VII of the Boston SPR published under Experiments with Physical Mediums in Europe (1928) he wrote "despite my studied and unremitting complaisance, no phenomena have occurred when I had any part in the control, save curtain movement which were capable of the simplest explanation."Prince also attended séances with the medium Jan Guzyk and came to the conclusion he had no paranormal ability.
Starting in 1924 He spent many months investigating Pearl Curran and published in 1927 his findings in a book titled The Case of Patience Worth. When commenting about his investigation of Pearl Curran and Patience Worth he is reported as saying “This is the most important known case of its kind.” And he is often quoted at the end of his investigation of Pearl Curran as stating that “Either our concept of what we call the subconscious must be radically altered, so as to include potencies of which we hitherto have had no knowledge, or else some cause operating through but not originating in the subconsciousness of Mrs. Curran must be acknowledged.”
You can read more about this man, his research and investigations at the link below.
Many of his findings were published in the magazine "Scientific American". Below is a list of the various articles.