Today in 1885, US Patent 322853 A was issued, an invention of Robert Reilly and Francis King, for their “Combined Bung and Faucet for Ale and Beer Barrels.” There’s no Abstract, although in the description it includes these claims:

Our invention relates to a combined bung faucet for beer, ale, and other casks.

The object of the device is to provide a bung normally closed by a spring-valve and the gaspressure of the contained liquid, and only opened by the introduction of the faucet.