On a trip with her mother to a sanitarium in Battle Creek, Michigan, they attended a lecture by Upton Sinclair, who had published The Jungle, where they met him.

[2] But in her autobiography, Craig said she never wanted to publish it because she found that "emotionalism and sentimentality among Confederate veterans made writing an objective study impossible.

[1] In her 1957 memoir, she described how she and her husband had collaborated on the work: Upton and I struggled through several chapters of Sylvia together, disagreeing about something on every page.

[5]Once married, she said they collaborated on a sequel, Sylvia's Marriage (1914), which was also published under Upton Sinclair's name, by John C. Winston Company, Philadelphia.

In his 1962 autobiography, Upton Sinclair wrote: "[Mary] Craig had written some tales of her Southern girlhood; and I had stolen them from her for a novel to be called Sylvia.

"[2] Her husband, Upton Sinclair, credited her with helping him to "write and publish three million books and pamphlets, flowing into every country in the world.

The book was criticized by science writer Martin Gardner who wrote "As Mental Radio stands, it is a highly unsatisfactory account of conditions surrounding the clairvoyance tests.