Mary Marshall was the first professional English medium. She introduced both Sir William Crookes and Dr. Alfred Russel Wallace to Spiritualism. Dr. Wallace began his experiments in the summer of 1865, and was especially impressed by spirit messages received through Marshall, who operated in full daylight. Although a stranger to Wallace, Marshal was able to tell him his brother’s name, where he died, and the name of the last person who saw him alive. Marshall produced rappings, caused a table to move and to levitate, and produced writing on glass—a forerunner of slate writing.
Thomas P. Barkas was the first to write about Mary Marshall in his book Outlines of Ten Years’ Investigations into the Phenomena of Modern Spiritualism (London, 1862). Marshall produced some direct voice from 1867 onward. At these, the spirit John King manifested.
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