Today in 1902, US Patent 710145 A was issued, an invention of John M. Dieterle, for his “Beer Cooler.” There’s no Abstract, although in the description it includes these claims:

This invention relates to new and useful improvements in beer-coolers, the object of my invention being to provide a self-cleaning beer-cooler and one which will be more sanitary in its operation.

As at present constructed beer-coolersI consist of a number of parallel communicating tubes having pipes for the ingress and egress of the beer extending from the same side of the beer-cooler. The beer is admitted to the cooler and ows therethrough to the pipe leading to the faucet. The pipes through which the beer runs, composing the cooler, necessarily gather a sediment deposited by the beer and become lined with organic matter, which is deleterious and unwholesome in the beer. Heretofore beer-coolers have been constructed with. end caps covering the ends of the several tubes, and an elongated brush has been separately inserted into each of these tubes for the purpose of removing foreign matter which accumulates therein. This means of cleaning the tubes is inconvenient because it is necessary to remove the end caps from the row of tubes, and, being inconvenient, this cleaning is likely to be neglected. Moreover, it is not as effectual as the means hereinafter described, for the use of which my improved beer-cooler is adapted.

In beer coolers as heretofore constructed there has always been a comparatively long line of pipe intervening between the cooler and the faucet, and the beer while passing through this pipe, after having been cooled, again rises somewhat in temperature, due to the fact that while the beer-cooler is surrounded by ice or other suitable cold-producing mediaA the conducting-pipe just referred 5o to has not been similarly cooled.

The objects of my invention, therefore, are threefold-first, to increase the frequency of cleaning beer-coolers by making it easy to do so, thus increasing the sanitariness of the process; second, to construct a beer-cooler which is self-cleaning, and thereby more effectually to cleanse the same, and thus conduce to a more sanitary method of cooling beer, and, third, to provide a beer-cooler so constructed as to be located adjacent to the faucet or beer-tap without the intervention of a pump ‘or long line of conducting-pipe.