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The History of Invisible Ink
As a kid I had a minor obsession with invisible ink after learning about it in a science club. An impressive stack of vinegar and lemon scented papers filled my desk, but the history of invisible ink is much more interesting than a summer enrichment program. Starting with the Roman general Pliny the Elder using milk from the thithymallus plant, to modern inks which are only visible under UV light, the science of invisible ink has grown quite complex. Some of the oldest CIA documents contain recipes for special inks, and MI6 and their very own "adult" mixture during WW1.
That's really his name?
Couldn't have asked for a better name...
... was "making enquiries for invisible inks at the London University".
From the last link:
Mansfield Cumming,
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
Dried semen shows under two well known "development" methods, both heat and UV. Better to use "ink" that only show under uncommon reagent, but that user would be reasonably expected to possess for another use.
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"Lost time is not found again."
and finally.... to develop it... and remember, this only works on April 1st... is to use a concentrated Plutonium solution wiped over the surface with an organic cloth like cotton or rabbit skin
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Did every MI6 agent get a stack of porn to use when writing hidden messages?
The Tao of math: The numbers you can count are not the real numbers.
Informative, but honestly who is going to need a gallon of invisible ink? And I quail at the thought of "mix it all together with your hands and dip a straw into it and suck it up into the straw"
Why can't we just make a very simple fountain style pen using a twig and pocket knife?
You missed the part where it was all an elaborate scheme to get you to suck up several-day-old urine in a straw.
Zing, successfully trolled :(
we're using a oxidized copper ion here
I am dying to know where is here, where you find yourself in common need of peeing in a jar to make invisible ink.
Bow before me, for I am root.
You missed the part where it was all an elaborate scheme to get you to suck up several-day-old urine in a straw.
BINGO! You win.
I, however, fail, because I meant to submit it as Anonymous Coward... oh well....
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See: http://en.wikipedia.org/wiki/Whitespace_(programming_language)
- David A. Wheeler (see my Secure Programming HOWTO)
Bet you cant
read that!