Over many centuries, block-and-tackle systems, or rope and pulley systems as they are more commonly known, have been used to help construct a variety of famous buildings, including the Colosseum in ...

San Francisco’s iconic cable cars are hoisted uphill by 35-year-old wheels called “sheaves,” which pull massive steel cables at 9.5 miles per hour. Now, those 25 underground sheaves will be rebuilt ...

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