The Metropolis

Your tax dollars at work: MI6 tried to make invisible ink out of semen

Darren Atwater | Thursday 23 September, 2010 17:38

Sit down kiddies, this goes way back, back to 1915:

Writing in his diary, deputy head of military intelligence at GHQ France asked the London University about invisible inks.

“In October he noted that he ‘heard from C that the best invisible ink is semen’, which did not react to the main methods of detection. Furthermore it had the advantage of being readily available.

Insert penmanship joke here — ed.

However, “at least one agent had to be reminded to use only fresh supplies of the ‘ink’ when correspondents began noticing an unusual smell.”

MI6 ‘used bodily fluids as invisible ink’ [The Telegraph]

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