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Crookes Tube with Maltese Cross
This Crookes tube has a Maltese Cross at one end. The tube is fired up with an induction coil. After a minute or two, the tube is tipped in the direction of the cross and the cross falls down. The viewer will notice at the end glass that the negative image of the Maltese Cross will stay on the screen for another minute or so. This occurs because the cross blocked the flow of electrons that changes the color of the end glass of the tube.

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Copyright 2003-2004 Howard Stone PhD.
stonevintageradio@gmail.com