Today in 1905, US Patent 783610 A was issued, an invention of Michael J. Owens, for his “Air Vent for Beer Barrels.” There’s no Abstract, although in the description it includes this summary:

This invention relates to certain new and useful improvements in air-vents for beer barrels and the like.

It has ‘for its object to provide a simple and inexpensive construction ot air-vent which may be quickly and positively connected or detached from the receptacle where employed, and more I particularly for use with a bung-socket such as illustrated and specified in patent No. 729,545, issued June 2, 1,903, whereby the beer-tap therein described is made interchangeable with the air-vent of the present invention. 1t is obvious with the use of the beer-tap described in the said invention that no supplemental means other than therein described is necessary to admit air into the barrel; .but many people prefer to use the ordinary spigot for withdrawing the contents, and in such cases it is necessary that air be supplied to replace the beer as drawn off. This has heretofore been accomplished by air vent plugs having’ tapered ends, which are driven into auger-holes made in the heads of barrels, a very unsatisfactory arrangement, for not only is it difficult to make a positive connection there between, but the tapering ends of the plugs have a tendency to split the heads from blows delivered upon the plug when securing the same in place, and where tliel.)ar1’el-he:uls are not destroyed by splitting the holes provided for the plugs are z’tli’ter ‘rei’ieated use so enlarged as to unfit them for continued service. I overcome the aforementioned objectionable features inherent to the aforementioned devices by the novel construction and combination of devices hereinafter explained.