He wrote that it was Clan MacKenzie territory, "full of woods" (it is treeless today), and that it was "guid for fostering of thieves and rebellis".

[9][13] The test was conducted as part of Operation Vegetarian, an ultimately unused plan which called for the dispersal of linseed cakes spiked with anthrax across the German countryside.

[9][14] It was recognised that tests would cause long-lasting contamination of the immediate area by anthrax spores, so a remote and uninhabited island was required.

[17] Eighty sheep were taken to the island and bombs filled with anthrax spores were detonated close to where selected groups were tethered.

[18] After the tests were completed, scientists concluded that a large release of anthrax spores would thoroughly pollute German cities, rendering them uninhabitable for decades afterwards.

The same day a sealed package of soil was left outside the military research facility at Porton Down; tests revealed that it contained anthrax bacilli.

Run-off from the formaldehyde seeped into the ocean and slowly led to the destruction of intertidal organisms such as barnacles, crustaceans, and seaweed.

[15] There was some confusion in which members of the public did not know it was being resold solely to its original owners and people from around the world sent letters to the British government asking to purchase the island for £500.

"[26] Local speculation believes the fire was set as an act of muirburn, a Scottish term when native moorland is burned to provide fresh growth for game and livestock.

It also features as the principal setting for the novel El año de gracia by Cristina Fernández Cubas, in which the protagonist spends a winter shipwrecked on the island.

[citation needed] In issues 187–188 of the comic book Hellblazer, in a story titled "Bred in the Bone", the protagonist's niece finds herself on Gruinard surrounded by flesh-eating children.

[28] "Smallpox Island", off the north-west coast of Scotland, appears in the 2000 AD comic strip Caballistics, Inc., although the warnings of contamination from biological weapons are a cover for a top secret, high-security prison.

The 2006 Doctor Who audio drama Night Thoughts is set on the fictional Gravonax Island, the name and history of which are inspired by those of Gruinard.