When was rolling luggage invented?
Rolling luggage was invented by Bernard D. Sadow in 1970. His invention was described in a patent, numbered 3,653,474, which emphasized the growth of air travel as a motivating use-case. The purported inspiration for attaching wheels directly to the luggage was an observation by Sadow of a porter stacking luggage on a rolling cart.
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Answer the following query.
When was rolling luggage invented?

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Rolling luggage was invented by Bernard D. Sadow in 1970. His invention was described in a patent, numbered 3,653,474, which emphasized the growth of air travel as a motivating use-case. The purported inspiration for attaching wheels directly to the luggage was an observation by Sadow of a porter stacking luggage on a rolling cart.
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