Blackstone, Harry (Henry Bouton). Blackstone?s Own Magic Trick Bubble Gum. Havertown, Penn.: Philadelphia Chewing Gum Corp., 1962. Original box (8 x 4 x 1 ??) with a complete set of 24 instructional cards, some accompanied by small printed accessories, including playing cards, a wooden paddle, and others. Box quite well preserved with usual creases and short tears not affecting the overall stability. The set was issued with a mini-poster, which is lacking, and the instructional cards are removed from wax wrappers, also not present.