In an 1872 advertisement offering spirit photographs for sale at thirty cents each or four for a dollar, Mumler lists “Last, but not least, three very wonderful pictures of Mrs. Fannie Conant, the celebrated medium for the Banner of Light.”

Banner of Light, a weekly subtitled “An Exponent of the Spiritual Philosophy of the Nineteenth Century,” had the largest circulation of any spiritualist paper in the world. For three dollars a year, subscribers would get “a first-class eight-page Family Newspaper containing forty columns of interesting and instructive reading.” Features included a literary section offering occasional French and German works in translation, but specializing in “Original Novelettes of reformatory tendencies.”

Banner of Light also featured reports of spiritual lectures by “able Trance and Normal speakers,” original essays on spiritual, philosophical and scientific subjects, general interest current events, and a very special service: messages from the dead.

The Message Department was described as “a page of Spirit-Messages from the departed to their friends in earth-life, given through the mediumship of Mrs. J. H. Conant, providing direct spirit-intercourse between the Mundane and Super-Mundane Worlds.”

Fanny Conant was prolific: the book Flashes of Light from the Spirit-World provided a 400-page compilation of questions answered by the spirits through her mediumship. The Biography of Mrs. Conant, subtitled Immortality Demonstrated Through Her Mediumship, was published in Boston by W. White in 1873.

Mrs. Conant held spirit circles (seances), open to the public, at the offices of Banner of Light:

“They are conducted through the mediumship of Mrs. Fanny Conant, a lady who for several years past has been influenced by spirits of every rank, grade of life, and development of mind. These invisible guests throng the circle room which the editors of the Banner of Light, with noble and exemplary generosity, open free to the public. And there, as opportunity permits, they pour forth, through the entranced organism of Mrs. Conant, the tale of their earthly lives, their vices and errors, their bitter lamentation for earthly lives misspent, messages of love and consolation to absent friends, warnings, encouragement, and every description of characteristic communication that could be conceived of as emanating from the heterogeneous conditions of human existence. And all this is represented in the voice, tone, gestures, and even the countenance of this wonderful medium, with such graphic fidelity that a witness with closed eyes might readily persuade himself, he was in the actual presence of all the various characters thus delineated. The accuracy of these remarkable spirit personations is further attested by hundreds of letters addressed to the Banner of Light by total strangers, who have read and recognized the printed messages from their spirit friends.”