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A few things to note, first:
Richard Trevithick built what could be called the first practical steam locomotive in 1804
Gas lighting for streets first was used in 1807
All the necessary ingredients for the cable car existed by about 1840
So: it wouldn't take much to push the steam locomotive earlier by a few years such that George Washington might possibly have seen one toward the end of his life; similarly, gas lighting could have become common before the War of 1812, and cable cars could have made their debut in New York by the Mexican War. Just for grins--and never mind the how/why--let's assume these three happened. How is the general pace of urbanization and technology accelerated? Larger cities sooner? Faster development of communications?