Well no, but if you’d like to pass as a local when you’re traveling in the British Isles, here’s the book you’ll want to read: Passport to the Pub: A guide to British pub etiquette.
It’s published by the Social Issues Research Centre, and the entire book is available free in html or pdf format.
Though it’s aimed at the tourists, much of it applies at almost any drinking venue; especially chapter 5, which covers the “Dos and Don’ts” of round buying, for example:
Don’t wait until all your companions’ glasses are empty before offering to buy the next round. The correct time to say “It’s my round” is when your companions have consumed about three-quarters of their drinks. (Beware: the natives tend to drink quite fast, and may have finished their drinks when you have barely started.) The exception to this rule is at ‘last orders’, when another round of drinks must be purchased even if everyone’s glass is full (see the next chapter for an explanation of this strange custom).
Do participate whole-heartedly in the round-buying ritual. Any sign of miserly penny-pinching will be noticed and frowned upon. There is no need to be excessively bountiful – in fact, ostentatious displays of wealth will not impress the egalitarian natives – but you must be seen to play your full part in the ritual.