Hoffmann, Professor, 1839-1919 · London : Frederick Warne · leaf 31
slight jerk to a depth of half an inch or so. Witha little dexterity the ball may easily be caught and retainedin the centre. This method is, however, scarcely legitimate.The ball should be rolled, and not jerked, into the desiredposition. No. IX.—The Electric Ball. This also is a French… … Fig. 9. middle of this projects a ring, D, and suspended from itsupper arm swings a little piece of strongly magnetized ironwire, E. A gilt cork ball, Ft into which are thrust six littleiron pins with their heads projecting, completes the appar-atus. The ball being placed on the open end of B B,…
Puzzles
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