|Description||Offshore test of biological weapons.|
Operation Cauldron is the code-name for a series of experimental bioweapons trials carried out from June until mid-September 1952 in a floating laboratory moored off Cellar Head in the Hebridean island of Lewis by the Royal Navy, in collaboration with Canada and the United States. The experiments, which involved spraying aerosol plague droplets on live monkeys, were organised by Dr David Henderson, head of the Porton Down germ warfare establishment. Dr Henderson had personally overseen the contamination of Gruinard island in Scotland during the Second World War, while developing an 'anthrax bomb'.
Enter the trawler Carella
In the final test of the Operation Cauldron series, the Fleetwood-based trawler Carella, with a crew of eighteen, ignored warnings to steer clear and unwittingly sailed through a cloud of plague bacteria (Yersinia pestis) on its return from a fishing trip to the waters around Iceland, causing concern about a possible plague outbreak around its home port in north-west England. A destroyer was dispatched from the Clyde, 400 miles south, with a supply of vaccine, and ordered to stay over the horizon, tuned to the Carella's frequency. If it picked up distress calls the Navy was to steam up and board the trawler. By good luck, it turned out that the aerosol plague droplets dispersed over very short distances. Which made the system ineffective as a weapon, but saved the trawler's crew.
The incident was dealt with at the highest levels of government, going through the First Sea Lord to the Chancellor of the Exchequer Rab Butler, who was deputising for the absent Winston Churchill. The event was successfully covered up at the time and, after the danger had passed, most of the documents relevant to the case were ordered to be burnt. Even the crew of the Carella were unaware of the incident until approached by a BBC documentary crew more than fifty years later.
|MOD video of Operation Cauldron|