Today in 1904, US Patent 749583 A was issued, an invention of Frederich Schmidt, for his “Beer Keg Washing Apparatus.” There’s no Abstract, although in the description it includes this summary:

This invention relates to improvements in apparatus for washing or flushing beer-kegs internally with hot or cold water.

The object of the invention is to provide an` apparatus by the employment of which beer kegs may be conveniently and expeditiously cleansed.

The invention consists in arrangements or combinations and constructions of parts, all substantially as hereinafter fully described, and set forth in the claims.