No one can say for certain who invented the fire hydrant. However the credit has always been given to Frederick Graff.
Frederick Graff Sr., Chief Engineer of the Philadelphia Water Works is credited with the first patent of a fire hydrant system resembling what we have today.
Mr. Graff was smart enough to obtain a patent back in 1801 for his idea of a post or pillar hydrant with valves and faucet functions. Unfortunately there is no official record of his patent since the U.S. patent office, and many patents including this one, were destroyed in a fire in 1836.
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