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Jack E. Leonard (1910 - 1973) was a comedian and actor, popularly frequenting the variety and game show circuit during the 1950s and 1960s. His film work includes roles in The World of Abbott and Costello (as the narrator) and Journey Back to Oz (as the Signpost).
Leonard made a guest appearance on The Jimmy Dean Show in episode 104, where he assisted in singing "Consider Yourself" to Rowlf the Dog.