Today in 1903, US Patent 726427 A was issued, an invention of William Haussermann, for his “Beer Filter.” There’s no Abstract, although in the description it includes this summary:

This invention relates to improvements in filters, and particularly beer-filters.

The object of the invention is to provide a beer-filter which is simple of construction, comparatively inexpensive of production, efficient in operation, and adapted to be readily and conveniently cleansed of the retained impurities.