Today in 1906, US Patent 812243 A was issued, an invention of Max Stahl, for his “Circulating System for Beer-Filters.” There’s no Abstract, but Stahl describes his invention as an improvement over then-current systems, saying his “invention aims to and does overcome the losses and disadvantages [mentioned earlier in the description], and in brief it consists of providing means whereby the column of beer can be switched off the racking-bench and continuously returned to the filter until stable relations are secured and the beer no longer runs cloudy or contains fibers of filter mass.”
