The fire hydrant is important tool in the fire service because it provides the water needed by firefighters to extinguish a fire. Fire hydrants are familiar sights on city street corners, though they are less common in rural communities where the fire service generally relies on other sources of water. The word hydrant- hydr- (water) + angi- (vessel) - came into the English language about 1828. Prior to that, fire hydrants were called fire plugs.
Why were fire hydrants called fire plugs and why are they still sometimes called fire plugs today? The term fire plug originated in the 1800s to describe the first efforts to acquire water from underground wooden water mains made of bored-out, crude logs. These logs were tapered at each end to fit together to form a "piping" system for carrying water. When a fire occurred, firefighters would bore a hole into this log main and collect the outpouring water in buckets or by suction hose. After the fire had been extinguished, wooden pegs- known as fire plugs- were pounded into the drilled holes to stop the flow of water. In some cases, the plug was already inserted into the wooden mains at half-block intervals. When the firefighters needed water, they would simply remove the closest plug.
Philadelphia was one of the first cities to successfully put into service wooden water mains with fire plugs. New York City and Boston followed later with similar water supply systems.
Today, fire hydrants are constructed of cast iron, and water mains are constructed of ductile iron, cast iron, or plastic underground pipe. With these types of fire hydrants and piping systems, pressures and pipe diameters have greatly increased. Because of greater pressures and larger diameters, more effective water supplies can be established to fight fires. Although the days of wooden fire mains and wooden plugs are gone, many people still refer to the fire hydrant as a fire plug.
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