Zufall, Bernard: Zufall's Memory Trix No. 6 Memorizing Facts and Figures ©1940 Bernard Zufall, NY Softcover, saddle-stitched, 5.5x8.5", 12 pages

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Comments: Memorizing Moves of Chess Knight, Miscellaneous Facts and Figures, etc. Zufall published a series of 6 volumes in the Memory Trix series, including:
No. 1 Magazine Memorizing
No. 2 Mental File Index
No. 3 Calendar Memorizing
No. 4 Memorizing a Deck of Playing Cards
No. 5 Memorizing Numbers
No. 6 Memorizing Facts and Figures

Contents (Partial, from page images, numbers are not page numbers):

1 Chess Knight Memory Feat
1 Effect: performer recites the full knights' tour on a chess board
1 Preparation
2 Chess Tour Code Words
3 Procedure
3 Memorizing Population Figures

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11 Biography of Zufall: extends to back page