The last remaining seltzer factory in New York City, Gomberg Seltzer Works, is at the end of the L train line in Canarsie, Brooklyn. Upon entering the dim warehouse on a quiet neighborhood street, the dusty light reveals a hulking industrial line dotted with blue glass seltzer bottles awaiting their carbonated contents. Old wooden crates are stacked Jenga style and pewter-tipped siphon necks from another century peek out like curious birds. Now in its fourth generation of operation, the factory—which opened in 1953 as one of about a dozen filling stations for seltzer men around the city—has, under 25-year-old Alex Gomberg, quietly diversified its services. When he left his job in education to join the family business (still run by his father Kenny and uncle Irv Resnick), Gomberg began shifting its deliveries to the new wave of New York bars and restaurants interested in local, handmade products. Now dozens of the city’s bars carry what may be the most authentic Brooklyn product around: New York City tap water, doctored with a bit of carbon dioxide and funneled into a nostalgic glass vessel. And it makes a hell of a gin and soda.