Plans to hold the First National Boy Scout Jamboree in Washington, DC had to be canceled because of an outbreak of Polio (Infantile Paralysis), a crippling and often fatal disease that now has been nearly eradicated. Plans for the Jamboree had been sufficiently advanced that Scouts had been chosen to attend. They had been formed into council troops and issued patches, neckerchiefs, and even troop flags. Thus quite a bit of memorabilia from the Canceled Jamboree still exists.
( 1) 1935 Jamboree Flags for Troop 1A-31 and Troop 1A-32.