London's microbiota - the Great Beer Flood of 1814

10 Jan 2020

London's microbiota - the Great Beer Flood of 1814

The Dominion Theatre stands at the southern end of Tottenham Court Road where it meets Oxford Street and Charing Cross Road. The Grade II listed theatre opened in 1929 and has contributed untold delight to lovers of musical theatre ever since. One notable recent offering, based on the music of Queen, ran for 12 years during which time the theatre’s frontage was graced by a massive statue of the group’s lead singer, Freddie Mercury, apparently having some form of seizure. Sadly though, I am not concerned here with the glittering achievements of British musical theatre but with another unfortunate event which occurred on the site more than 200 years ago – the Great Beer Flood of 1814. 

In the 18th century, a new beer, strong, dark, aged and bitter, became increasingly popular in London, eventually dominating the market. Called by the brewers ‘entire’ or ‘entire butt’, the precise origin of the name is obscure but may have derived from the practice of combining the wort obtained from several mashings of a single charge of malt to brew one beer: hence ‘entire’. Its popularity among porters – at the time a large section of the working-class population employed in carrying loads around London and unloading ships in the Thames – led to it being more commonly known as ‘porter’.

Porter brewers used what was known as ‘high blown malt’, a malt that had been rapidly dried at high temperature so that it had popped like popcorn, had acquired a dark colour through extensive Maillard reactions and possessed relatively low amylase activity. It was the first beer suited to very large-scale production. It could be brewed at higher temperatures than other beers and, in the absence of artificial cooling, this meant that the brewing season could be extended into the warmer months and that larger fermentation vessels could be used because heat retention was less of a problem. Porter production also required higher capital investment since the product had to mature for about 12 months before consumption to clarify and develop its characteristic taste. The latter is thought to have been due in part to the activity of Brettanomyces species, nowadays generally regarded as beer spoilage organisms.

As production and demand grew, conventional butts (108 gallon casks) were replaced by increasingly large vats for maturation, setting up a competition between brewers over who had the demonstrably larger vat. A visitor to Thrale’s brewery in Southwark in 1775 described a dinner for 100 people held in an empty vat with a capacity of 54,000 gallons. In 1790, 200 people dined in a new 60 ft diameter vat at a Clerkenwell brewery. But scant regard was given to safety aspects and this hubris had its inevitable consequence.

Where the Dominion Theatre now stands was previously occupied by the Horseshoe Brewery, acquired by Henry Meux in 1809, and largely devoted to the production of porter. On 17 October 1814 one of the iron retaining hoops on a 22 foot high maturation vat fell off. A little later the vat burst launching a flood of 570 tons of porter in a wave of beer and debris which damaged other vessels, demolished the wall of the storehouse and flooded out into the surrounding area. There it destroyed the back wall of a nearby pub and flooded cellars in the overcrowded and insanitary slums of the St Giles ‘rookery’. Eight people died of drowning – all women and children. It was said that the death toll would have been much higher if the vat had burst later in the day when more people had been at home.

In the aftermath, the tragedy was ruled to have been ‘an act of God’ with no one responsible and the fortunate brewery was even able to reclaim the duty it had paid on the lost beer. Rather smaller amounts were collected for the families of those who had died. One story told was that of an enterprising soul who exhibited the body of a drowned relative to view for a small fee. This proved so popular that the weight of the crowd gathered in the room proved too much for the floor which collapsed, precipitating them and the body into the cellar which was still knee-deep in porter.

The brewery continued in operation for another 100 years but was closed in 1922 and demolished the following year to make way for the theatre. Aesthetically it appears not to have been much of a loss since it was described in the press at the time as ‘frankly hideous’.


Martin Adams
SfAM President 2011-2014