As someone mentioned in the comments (and the post author dismisses), a reasonable version of this myth might be constrained to sailing. I found an okay discus

As someone mentioned in the comments (and the post author dismisses), a reasonable version of this myth might be constrained to sailing. I found an okay discussion on it here: http://boards.straightdope.com/sdmb/archive/index.php/t-200849.html http://boards.straightdope.com/sdmb/archive/index.php/t-2008... There's a reference to "Purser's Instructions", where apparently it is mentioned that the Royal Navy sailors were allotted 1 gallon of beer per day. I tried finding it online, but couldn't find the text. Kind of blows my mind that in 2015 I can't just easily read any book that is more than 250 years old.