My version of this story is from high school chem class. Somehow a lab partner and I convinced our teacher to let us test "which gunpowder mixture burns best". This was a several week long "student run experiment" type project, culminating with presentations in class. One component of the presentations was a demo - we chose to show the difference between the worst performing mix and the best performing mix. The "slow mix" made a ton of smoke and stunk up the whole wing of the school w/ suphur. The fast mix cause enough thermal shock to shatter the crucible we used - pieces went everywhere doing a little damage to the audience even: one kid's notebook caught on fire because some of the power landed on it. Another kid had a freshly melted hole in his big pants (it was the mid 90s) - I'm glad no one was hurt. We got an A, but younger folks told me that in later years fire experiments were banned.

The only lesson I managed to learn was: It's important to do bold stuff before everyone else, because you either get to have fun or deal with the rules that the fun people caused.

I'm not sure that's a great lesson, but I have yet to see it violated.

Our teacher would do a simple demonstration every year with a small piece of sodium and water. The plan was to have the small piece of sodium fizz around in the bell jar of water. He kept pulling off pieces of sodium that were too small, and they just went “pfft”. After the 5th failed attempt, he was mad and pulled off a large chunk, and he tossed it in the water. It didn’t dance around, it went <BOOM>, big <BOOM>, two feet from the students in the front row. I was 12 feet away and got wet and was hit with glass. He barely kept his job. It was awesome!

BTW, the lab table in our tiered lecture room was nearly 6ft/2m from the first row of seats and for the exercise the teacher had a sheet of perspex in front of the experiment (perhaps it'd happened to him with an earlier lot of students).

Halfway through class we figured out if we put enough in the plastic container, it would create little dry ice bombs that would explode due to the pressure. So we started doing that and tossing it at people around the room.

(No injury or [unintended] property damage incurred, but The Adults quickly realized that we hadn't actually broken any rules, and there definitely should have been rules to be broken.)

Oh man, I dread this - as kids, my parents would ride random horses they found in a field and come hone late,I walked to school alone at age of twelve before mobiles ,and kids these days have no freedom at all

I'm firmly of the belief that keeping kids walled up behind glass and protected from life's knocks when young is one of the significant reasons for why many later lack resilience and develop emotional problems.

You can make an equivalent functional microscopic 'pipebomb' with just matchstick head scrapings and the plastic body of a pen. This usually does produce a small satisfying bang and the risks of screwing it up are mostly limited to 'very nasty burn'.

Stiff cardboard tubes, packed clay, and low explosives like plain black powder, flash powder, etc provides all the confinement you need for a bang and a flash. Thermite is also fun, and so long as you're not igniting it on top of a car battery still filled with acid, it's quite a bit safer.

You can also go the slow pyrotechnic route with making smoke bombs. It's not as simple as it may appear, but from a hazard point of view nothing is going to explode. So long as you take some basic fire safety precautions like doing it outside away from structures and flammable materials on a hot plate it's safe and entertaining. Couple of safety tips, if you're grinding up your oxidizer in a coffee grinder (definitely recommend, mortar and pestle suuuuuucks) make sure you never use it for anything other than oxidizers in the future. If you use it to grind up a fuel later on there's a very good chance you won't get every last trace of oxidizer out so you could wind up with a bit of powdered fuel and oxidizer mixing together in the tiny joint between the blade and the bowl and completing fire triangle bingo. Another foundational precaution is to have a good understanding of what your ingredients are because getting it wrong can be quite hazardous, not just disappointing. For example a friend of mine in high school wanted to make some smoke bombs and was asking me for directions. I told him to find some stump remover from the hardware store and make sure it was plain potassium nitrate. He couldn't find it on the bottle and assumed it probably was and figured it would either work or it wouldn't. That bottle was filled with sodium metabisulfite instead of potassium nitrate and when he tried to heat it with sugar to melt it together it started decomposing into sulfur dioxide gas which combines with moisture in mucous membranes to form sulfuric acid. He had chemical burns in his throat and was coughing for a bit afterwards but luckily no lasting damage.

Another fun misadventure with the same friend. We came up with the brilliant plan of stuffing an entire gross (144) of bottle rockets into a huge pickle jar that was the perfect height to hold the body up over the mouth of the jar. We sprayed the fuses all over with starter fluid (ether, not lighter fluid), lit the bundle, and ran back. Moments after they started launching the heat from the exhaust (and the ether might have been a contributing factor) shattered the pickle jar and now all of the remaining rockets are splayed out in every direction horizontally. We ran and dove with rockets going everywhere and these were the ones with a healthy report at the end too so it's basically just launching fire crackers at us.

I'm not going to try to tell anyone not to play with fire, but please show some modesty and act responsibly. Everyone makes mistakes and overlooks things. Plan for this, expect it, and position yourself so the fallout for things going sideways doesn't involve the fire department or the coroner especially when your latest escapades involve showing your friends. They're idiots, they will do dangerous things out of ignorance. Don't put someone else in a position where they need to know anything other than stay behind that tree and don't come out if it doesn't go off. They aren't going to stop drop and roll, they're going to panic and make things worse like running with a flaming gas can spreading fire all over the place. Aggressively plan for failure because things will go wrong and you need to be able to deal with that when it comes up.

1. Milling the powder makes it a lot more effective. My buddies and I would make ball mills with old washing machine engines, and whatever non-sparking material we could find for the balls.

2. If you want it to explode rather than burn you have to granulate it. Wet it and let it dry, and grind it a little bit and pass it through some mesh to grade it.

The raw powder is good for making rockets, but it won’t very readily explode.

My friend and I took the powder out of fireworks and into a spend CO2 cartridge like you did. We used an M80 fuse and had a similar experience as you, some fizzing but no bang. Based on ideas in the Anarchist cookbook we sawed open shotgun shells and tried to get the gunpowder out. I think it was mostly sawdust mixed with buckshot and little gunpowder. No bang. My fiends brother caught us and said dude you’re making pipe bombs so we stopped.

Anyone else heard of the anarchist cookbook in the early internet days?

I don't think most ever took it seriously, it was just an antiauthoritarian status symbol of the early internet. It was a badly-written compendium of nefarious bits and pieces collected by the likes of youngish teenage boys. I suppose the powers that be would now consider it dangerous material and its possession deemed suspicious. That said, go to the chemistry section of any library and you'll find much more subversive info therein.

BTW, when I was at school a part of the chemistry curriculum was to make and prepare black powder then test it. Moreover, the complete chemical equation of the reaction was in our textbooks and we had to understand it. Not only was the explosive reaction presented as just one equation but also it was subdivided into its constituent parts, sub-reactions etc., so that one fully understood the chemistry. That's to say we had to know how to calculate proportions for full combustion, etc.

Being allowed to officially make black powder under the auspices of the chemistry teacher made chemistry fun. Oh, how times have changed. Boring!

Making guncotton/nitrocellulose, picric acid, etc. isn't that hard. In fact, as I've mentioned elsewhere in these posts, I made nitroglycerin in the school lab. (note I'd strongly advise those tempted not to do so - even if you're a good and careful chemist, as such acts are frowned upon with much greater severity than when I did it decades ago).

The fact is that with the type of training we students had had, by the time we'd finished five years of high school chemistry we could make most of those chemicals by following the procedures for doing so. It was only at university we eventually got to understand the underlying theory behind why those procedures were formulated the way they were.

BTW, about the only chemistry I do these days is to figure out what's the best prepackaged cleaner to use in the kitchen. :-)

Thank god I never boiled bleach to try to make plastic explosives.

I grew up pre-internet. A high shcool friend had a copy of that book, but we never used it for much. Found our own fun.

We were just boys being boys back then, I'm sure we'd be in big trouble with those things now. Do not try this at home.

https://www.amazon.com/U-S-Army-Improvised-Munitions-Handboo...

Don't mess with primary explosives though. They're either too difficult to manufacture cleanly in an amateur setting or too unstable to be made by anyone who isn't a complete moron.

Oh, and then there was Mr. Wizard……

[1] https://tfwiki.net/wiki/A_Decepticon_Raider_in_King_Arthur%2...

Right, fortunately most of us survive such experiences a little the wiser. If you read my post below then you'll see we officially made black powder as part of our school chemistry curriculum. I've often thought that the reason for its inclusion was twofold, the first being that it made chemistry fun as bangs and pops amuse most kids, but second that it was an excuse to control the environment in an era when kids had much more ready access to dangerous chemicals than nowadays.

By explaining the dangers of making black powder such as ensuring one mixes components in a mortar and pestle of a type that cannot generate sparks, mixing one's ingredients slightly damp then drying later and preparation in small batches, etc. then kids get the safety message early on.

The safety message was never lost on me. As I mentioned in a HN post ages ago, I unofficially made nitroglycerin in the school lab one lunchtime - right, that was never on the curriculum - but I reckon I did so safely. First I was careful to inform myself of the facts. Not only was I scrupulosity careful with the temperatures and the ratios of the critical ingredients but the quantity that I made was just sufficient to prove that I could actually make it. To this end, with the exception of acid-neutralizing sodium carbonate soln., I measured the crucial chemicals out strictly in eyedropper amounts - as that was the practical minimum I could make, so I ended up with only a drop or so of the product (which, I did eventually make go bang).

Nothing went wrong because we were constantly drilled in safety. The point is safety was always stressed in our chemistry classes by our teachers. Such instruction wasn't only done when making black powder but also with any dangerous process and or production of dangerous chemicals, for example, poisonous hydrogen sulfide had to be prepared in a Kipp generator in the fume cupboard - with no exceptions whatsoever. Essentially, good lab practice was an essential part of our coursework.

We had access to many dangerous chemicals that you'd never see in school labs today, mercury - pints of it, carcinogenic benzene, hydrofluoric acid, metallic sodium and potassium, uranium (as disks about twice as thick as quarter), radioactive alpha and beta sources and we prepared fuming aqua regia to dissolve tiny bits of gold leaf and so on but we were always taught safety measures before we handled them.

(What horrifies me these days is that the modern approach to safety is to simply remove or ban these dangerous substances altogether, especially so from classrooms.

By not exposing kids and even university students to them under safe, strictly controlled conditions, we're breeding a race of people that are fearful of anything that's classified as a chemical. We've now a population that's disproportionately fearful of all chemicals and this is not helpful when it comes to having to distinguish between what's truly dangerous and what requires, say, careful handling/disposal.

For example, these days, the very mention of mercury or any of its compounds to the GP and you'll get almost the same reaction or level of horror no matter what form or chemical formulation that the element comes in. I cannot think of a better example of how potentially dangerous this fear without a sense of proportion can be than with mercury. At one end of the spectrum we've metallic mercury, a comparatively dangerous metal, but not so dangerous in that we've used it in amalgam form in our teeth for centuries and the population is still here alive and kicking but at the other extreme we've dimethylmercury which is just about the most grotesque and dangerous of chemicals known.

Overly isolating the population from chemicals and stopping students from having early hands on experience to potentially dangerous ones (no, not that one) at school and university under safe controlled conditions leads to this loss of a sense of proportionality. In my opinion, this is not a helpful state for society to be in.)

Incidentally, I forgot to mention above that not that long ago I'd come across a person who had never actually physically seen mercury even though having studied chemistry at high school. To me, it's indicative of how far things have come since my formative years.

"Hmm... so these guys want us to give them money to fire a bunch of medieval cannons with pre-industrial gunpowder."

Does anyone know if this happened (it seems a plausible idea to me)?

What? That's absurd. Food processors would never do such a thing. They only use the finest cultured celery powder (filled with "all natural" sodium nitrite).

My parents were believers in not reading children’s books but actual novels to me, at ages 4+ and they went through most of Verne’s novels, but I will never forget that particular one.

Bootstrapping civilization from literally nothing to gunpowder, steam engines and telegraphs was mesmerizing. I think this was the time I decided I wanted to get involved in engineering in general. I mean McGyver is nice and all but I’ve not seen anything come close to scope and ingenuity as a literary work since.

is this true? how about adding salt to ice to make it colder?

fermentation creates heat, was it ever scavenged for anything?

Just curious but it seems like there might have been some other thermic chemistry over the years.

Good fuse from hobby shop (for Estes rockets I guess). CO2 cylinder. It's a nice little bomb

‘Tis essential for powder making.

Hic.