Houdini's 19-week run at the Hippodrome began on January 7, 1918, during which time he debuted his famed 'vanishing elephant' trick, making this letterhead significant. The letter also has ideal magic-world content on the subject of the Society of American Magicians (S.A.M.) and a reference to "Martinka," founder of the famous magic company that was eventually owned by Houdini as well.
Please see photos for condition as this item has evidence of soiling and creasing. The item will include a full Letter of Authenticity from Beckett Authentication Services.