How did they keep the beers cold in the saloons of the Old West?

Saloons also served up volumes of beer, but in those days the beer was never ice cold, usually served at 55 to 65 degrees. Though the beer had a head, it wasn't sudsy as it is today. Patrons had to knock back the beer in a hurry before it got too warm or flat. It wasn't until the 1880's that Adolphus Busch introduced artificial refrigeration and pasteurization to the U.S. brewing process, launching Budweiser as a national brand. Before then, folks in the Old West didn't expect their beer to be cold, accustomed to the European tradition of beer served at room temperature.

http://www.legendsofamerica.com/we-saloons.html

The White Elephant bragged that it served 'the best brands of old sour mash whiskeys in the state' as well as 'ice cold' beer. The first was a demonstrable boast; the second was possible only after the Crystal Ice Company began manufacturing the stuff year-round starting in March 1887.

http://www.historynet.com/fort-worths-wild-white-elephant-saloon.htm

From the late 19th century to mid 20th century, in cities and towns icemen would commonly make daily rounds delivering ice for iceboxes before the electric domestic refrigerator became ubiquitous.

https://en.wikipedia.org/wiki/Iceman_(occupation)

In the Western United States, most often referring to the period of the later half of the 19th century, between the American Civil War and the end of the century.

https://en.wikipedia.org/wiki/Old_west

Cold mountain streams were used, as well as root cellars.

https://en.wikipedia.org/wiki/Root_cellar

Also, it should be noted that beer was not artificially carbonated. The slight natural carbonation required only that it be cool to be refreshing and tastey. Modern beer, with its artificial carbonation, needs to be very cold to hide the sharp taste of the excess carbon dioxide.

https://www.quora.com/Was-beer-carbonated-in-the-Old-West
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