A Jacob's ladder is a folk toy consisting of blocks of wood held together by strings or ribbons. When the ladder is held at one end, blocks appear to cascade down the strings. However, this effect is a visual illusion which is the result of one block after another flipping over.
The mysterious movement of this puzzling toy has fascinated generations of American children. Described in Scientific American (1889) as a “simple toy – very illusive in action”, the Jacobs Ladder still confounds us with its seemingly inexplicable motion.
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