Today in 1917, US Patent 1232098 A was issued, an invention of Heinrich Schneider, for his “Process Of Leaching Out Hops.” There’s no Abstract, although in the description it includes this summary:

The object of the present invention is a process of leaching hops in a hop extracting apparatus provided with a strainer and stirring device, but passing the wort and after-wort through the hops on their way between the refining vat and the copper.