By the corner of Moss Street and Grand Route St. John, in the city that lays claim to the oldest continually operating bar and the first “cocktail,” you’ll find the rusted remnant of a very different type of innovation in hydration.

This oxidized hydrant along the bayou is easy to miss. The tiny piece of engineering, which was installed at its current location in 1869, represents not only the oldest known fire hydrant in New Orleans, but also a major technological advancement. It bears the date of the patent that revolutionized firefighting technology.

As New Orleans didn’t have a public water system until the late 19th century, prior to this time firefighting relied largely on the volunteer force’s ability to literally throw water on conflagrations from the city’s four fire engines.

Enter Birdsill Holly, whose count of U.S. Patents was second only to Thomas Edison. His hydrant allowed firefighters position their equipment closer to the blazes they were combatting. In New Orleans, the hydrant let them pump water directly from the bayou, with added pressure to make attached hoses radically more powerful and efficient.

Eventually this model was adopted by thousands of North American and European cities (including Chicago, but not until after the Great Chicago Fire). While Holly is often erroneously credited as the inventor of the fire hydrant (other patents predate his own), his modifications and improvements unquestionably saved countless lives.