When Ian Fleming’s James Bond novels were first being published, within the story line was a tale of the KGB using a simple little squirt gun filled with a fluid containing cyanide. A squirt or two in the face was enough to do the job.
So, in 67 years, we have moved from a squirt gun, to a dart gun. Wow.
I first heard of a weapon like this many years ago.
It was speculated then, that's how Adlai Stevenson -- former Illinois governor, Dem presidential candidate and UN ambassador under Presidents Kennedy & Johnson -- had died so suddenly in 1965, while walking in London.
Prussian Blue.