One hundred years ago, in the autumn of 1917, Bolshevik Red Guards stormed the Tsar’s Winter Palace in Petrograd, an event immortalised by the great Russian film director Eisenstein in his film October

Not surprisingly, such epoch-defining moments rather overshadowed a more modest outbreak of civil unrest that occurred in England at about the same time and one that is more redolent of an Ealing comedy than an Eisenstein epic.  

In an otherwise tranquil Cambridge, the police were called out to defend horse chestnut trees from marauding bands of children who were energetically attacking them to collect horse chestnuts. ‘Conkers’ had always been subject to limited harvesting for use in contests where, strung on a string, they would be viciously scythed through the air as competitors tried to destroy their opponent’s conker (and occasionally their knuckles!). In 1917 though, there was a new impetus to the harvest as conkers had now been identified as an important national resource. Behind this lies a milestone in the history of applied microbiology: acetone butanol fermentation – the first microbiological process to require asepsis on an industrial scale. 
 
From its beginning, the First World War had seen unprecedented demands for cordite, a smokeless propellant for naval guns and other artillery. Acetone was used as a solvent in its manufacture and existing supplies, produced largely by the destructive distillation of wood, were nowhere near sufficient. A fermentation process using potatoes had been developed before the war by a consortium based in Manchester, London and Paris, centred around Strange & Graham, Technical Research Chemists in London’s City Road, but it had not proved very successful in practice. Chaim Weizmann, a lecturer at the University of Manchester, was a member of the consortium but had been sacked in 1912 after disagreements about money and recognition. Following his dismissal, he continued to work on the project independently, going on to isolate the bacterium now known as Clostridium acetobutylicum, which could produce acetone reliably and in useful quantities from maize. He offered this to the government who, in 1915, provided him with pilot facilities to prove the process at Nicholson’s Three Mills Gin Distillery on the River Lea in Bow, East London. 
 
Nicholson’s started in London during the 18th century ‘gin craze’ and produced the popular Lamplighter London Gin at distilleries in Clerkenwell and at Three Mills. The company enjoyed impeccable establishment connections through parliament and cricket. William Nicholson, the company chairman, was a Liberal Member of Parliament for Petersfield and his father, also an MP, had been an enthusiastic cricketer – so much so that he had loaned the Marylebone Cricket Club (MCC) the money to buy Lord’s cricket ground in London. One reward for this generosity was that the MCC adopted Nicholson’s colours – bright yellow and red – as their own. To this day, the same colours adorn the club’s famously migraine-inducing tie in honour of Nicholson.  
 
Successful gin production does not require strict asepsis and the facilities available at Bow meant that problems of contamination bedevilled acetone production there. Nonetheless, sufficient promise was shown for it to be rolled out to a distillery in Scotland, an existing (previously unsuccessful) acetone factory in King’s Lynn and a large, newly built plant at the Admiralty cordite factory in Dorset. It was further proposed to take over all UK distilleries for this purpose: a plan that was greeted with some dismay when Lloyd George announced it to the distillers at a meeting in February 1916. 
 
In the event, to the relief of the distillers, this did not happen since it was recognised as more cost-effective to use valuable shipping to import acetone produced where maize was grown in North America rather than maize to produce acetone locally. The process did, however, continue on a quite substantial scale at the four existing sites in the UK so there was considerable interest in reducing its reliance on imported maize. 
 
The possibility of using horse chestnuts was first mooted in April 1917 and Weizmann’s advice sought. He was no longer working at Three Mills but had moved across London to laboratories, first at the Lister Institute in Chelsea and then across the river at Point Pleasant, Wandsworth. Test results showed horse chestnuts could be used, although pre-treatment was required to reduce levels of an inhibitory glycoside, aesculin, and the fermentation sometimes foamed excessively. 
 
Following this success, a national horse chestnut collection scheme was devised and outlined in a government circular to local education authorities issued in August. It emphasised the value of horse chestnuts as an alternative to maize in ‘certain industrial processes which are essential to the prosecution of the war’. Under the scheme, horse chestnuts were to be left at local centres from where collection would be arranged. 
 
Seizing an opportunity to support the war effort, the patriotic zeal of youth knew no bounds and elderly citizens were distraught to see their trees under enthusiastic and noisy assault by unruly bands of small people, occasionally hotly pursued by breathless policemen. Despite this, more than 2,000 tons of horse chestnuts were collected, though failings in organisation meant that many tons were also left rotting at collection points. The scheme was considered sufficiently successful for discussions to be held on improvements for the following year although, in the event, it was not repeated and the war ended in November 1918. 
 
With peace, the distillery reverted to its former role until it was bombed during the Second World War – an event that occasioned one of the many tales of selfless bravery characteristic of the blitz when unnamed local heroes risked their all to dive into the River Lea and save six barrels of spirits from being lost. Today, though no longer a distillery, several of the original buildings survive as part of London’s largest film and television studios: 3 Mills Studios.