Penetration Frame. New York: Ludwig Krug, ca. 1935. A solid sheet of glass secured in a chrome metal frame is pierced by a pencil yet remains unharmed and without a hole when examined minutely by spectators. 5 x 4", with “patent applied for" stamped to one side (later models listed Krug's patent number). From the fabled collection of Charles Larson, the New York automotive dealer whose treasures were featured in the pages of Greater Magic. Accompanying the standard Krug frame is a matching ungimmicked “front" constructed expressly for Larson, who switched the gimmicked and ungimmicked frames when performing the effect for fellow magicians. So popular was the Krug version of this effect upon its release that nearly every well-posted amateur and professional magician was familiar with its working. Includes a black felt case for switching frames.