Beer code

The codes used in the 19th century to designate different beers fascinate me. I'm talking letters and numbers. All those X's and K's. And numbers, too, like Bass's No.1 to No.6. But what the hell do they mean?

I'm pretty sure I've cracked the X's. They are the simplest method of strength indication. The most likely explanation for their origin is, as so much about beer, all to do with tax. Pre-1830, there were, for tax purposes, two classes of beer: Table Beer and Strong Beer. The former was taxed at the rate of 2s 6d per barrel, the latter at 10s.

There were strict rules about marking and keeping separate the two types of beer. One of the simplest fiddles was to mix Table and Strong Beer and sell it as Strong. Judging by Accum's analyses, in the first decades of the 19th century this practice was rife. I know for certain that barrels of Table Beer had to be marked with a "T". Barrels of Strong Beer it seems were marked with an "X". Depending on which explanation you believe, this either stood for "eXcise" or was simply the Roman numeral for 10 (the tax in shillings).

The number of X's used, give an indication of a beer's strength. In the early part of the 19th century, breweries usually produced a range of Ales, ranging from X to XXXX, though you occasionally see XXXXX. This system was mostly used to designate Mild Ales, that is Ales sold unaged. Mild did not mean weak. XXXX Ales had gravities up to 1100. X's were also use for Porter. Though a P was often stuck on the end to make it differentiate the names from those of Ales. Guinness called their Porter X, Extra Stout XX and Export Stout XXX. As X's came to be associated specifically with Ales, they were sometimes replaced by S's. Whitbread, with S, SS and SSS is a good example of the use of this naming convention.

Breweries produced a second range of Ales. Stock or Keeping Ales. These were aged before sale. In the first half of the 19th century, these were often designated XXK, XXXK or XXXXK. But, as the century progressed, the names were mostly changed to just K's. So KK, KKK and KKKK. Typically, a brewery would produce X, XX, XXX and XXXX Mild Ales and KK, KKK and KKKK Stock Ales. The equivalent K and X Ales (for example XX and KK) had the same gravity. The only difference was a slightly higher hopping rate for the Stock Ales. Though no-one seemss to have bothered ageing the weakest Ales, so you don't find K Ales.

By around 1900, breweries had reduced the number of X Ales they brewed. The London breweries usually only made one, X. The stronger Mild Ales had mostly died out. The range of Stock Ales had thinned, too. Typical for London breweries was KK and KKK. As ageing went out of fashion, these came to be known as Strong Ales rather than Stock Ales. KK, or Burton as it was usually called in London pubs, was a standard draught beer between 1900 and 1950.
Here are a few random examples from London breweries:

Griffin Brewery Ales 1839
X 1073; XX 1089; XXX 1105
KK 1089; KKK 1105
(Source: Griffin Brewery brewing records)

Griffin Brewery Stouts 1844
S 1073.4º
SS 1087.3º
SSS 1097º
(Source: Griffin Brewery brewing records)

Whitbread Stouts 1873
S 1070
SS 1077
SSS 1091
(Source: Whitbread brewing records)

Barclay Perkins Ales 1869
X 1060; XX 1080; XXX 1093;
KK 1079; KKK 1093; KKKK 1106
(Source: Barclay Perkins brewing records)

Barclay Perkins Ales 1880
X 1060; XX 1079; KKK 1090
(Source: Barclay Perkins brewing records)

Some names, need no explanation. I think most of you have an idea what PA and IPA stand for. Others, have me flummoxed. AK, for example. How I would love to know what that stands for. Or derivatives like AKA and AAK. Answers on a postcard, please.