This thing came across my radar screen:
In science, a 'Binary compound' is a chemical compound containing two different chemical elements.
A binary explosive is an explosive made of two components that become explosive when mixed.
A binary chemical weapon contains two chemicals that when combined make a toxic agent, such as featured in the 1972 novel Binary by Michael Crichton (writing as John Lange):
My professional opinion as a Special Forces engineer: I believe this is an explosive similar to fulminate of mercury ( Hg(CNO)2 ) used in percussion caps (primers) and blasting caps, or perhaps nitrocellulose (a.k.a. guncotton), both of which have been around for at least a hundred years.
Primers are a lot more powerful than people give them credit for, but they are not THAT powerful. This substance, while explosive, does not actually 'vaporize' the watermelon; rather, it pushes it off the post. Still, if you didn't know what you were doing, you could blow some fingers off.
BE ADVISED: DO NOT experiment with creating such substances in your home, using information gleaned off the Internet. Not only are such chemical reactions subject to variances due to standard temperature and pressure (remember the Underwear Bomber's bomb failed to detonate, but it still burned his entire 'manly package' clean off); the recipes contain intentional inaccuracies, planted there for wannabe revolutionaries to blow themselves up before they can harm the general public.