In common with all of Bongo's notes, these are illustrated only and do not explain the effects with text. They were aimed to be a memory aid, not instructions, so the reader needs to either be familiar with the material or use the drawings as a starting point to create the apparatus and figure the effect and method out for themselves. These are signed on the back cover.
 
Condition: Fair, a worn ex-library copy with a sticker to the front, inscription to the inside front cover,  pencil drawing to rear cover, marks and wear throughout. 
 
Binding: Booklet
Year:  1980s
Publisher: Ali Bongo
Pages: 8
Dimensions (to nearest cm): 20 X 16cm