[adityaathalye]

Excellent work, glinscott. Thank you for sharing! I am about to send this to all my pals who are parents to schoolkids (um, and also pals who are still, like me, basically a schoolkid :p XD).

Building things up from first principles, and ideally also tactile / visceral examples, is my absolute favourite genre of explanations. Alas, a rarefied genre, because it is so much harder to do well (without doing disservice to the learner's intellect and ability) than expert talking to (presumed) expert. So thanks for contributing to it.

People like George Polya [0], Richard Feynman [1], Grace Hopper [2] are exemplars of this tradition.

[0] https://www.youtube.com/watch?v=h0gbw-Ur_do

[1] https://www.youtube.com/watch?v=EKWGGDXe5MA

[2] https://www.youtube.com/watch?v=ZR0ujwlvbkQ

(And I too try in my own meagre way through my blog and source code, albeit it's all plain text because visual explainers, animated ones that too are ridiculously difficult. So I have some idea of how much of a labour of love your piece is. <Claps hands, Whistles, Doffs hat>.)

[glinscott]

You are welcome! I agree, it's a really nice way to learn about something. Digging into the transfer of power with belts may have been one of my favorite parts here, even though it's not really steam directly :).

[Animats]

The capstan winding animation is beautiful.

The key thing to understand about early steam engine technology is that they didn't have steel. Good steel in quantity wasn't available until the Bessemer converter around 1880. The converter itself is simple. It took about 10,000 melts to get the metallurgy right, and analytical chemistry to get consistent ingredient mixes.

Without steel, the early engines were cast or wrought iron. So everything was very low pressure, or blew up. That's why "atmospheric" engines such as Newcomen's were built. That doesn't use steam pressure at all. It just uses condensing steam to create a partial vacuum so atmospheric pressure can push the piston. The technology got stuck there for 75 years.

Higher pressure engines made of iron were tried. They blew up frequently at first. This led to a useful institution, The Hartford Steam Boiler Inspection and Insurance Company, founded in 1866.[1] They still exist, owned by Munich Re. Hartford Steam Boiler had a tough approach to insurance. They'd insure risky things such as steamboats, but only after their inspectors had inspected them. Their insurance policies gave them the right to inspect at any time, which they used. The usual arrangement was that they inspected something, produced a list of things which had to be fixed, and came back for a second inspection after the fixes. Only then did they provide coverage. Steamboats mostly stopped blowing up.

(Today, Hartford Steam Boiler also sells business interruption insurance against cyberattacks, and even AI liability insurance. They probably still inspect first. That may be the good path to AI safety - liability lawyers suing for damages on one side, and an insurance company into tough inspections on the other.)

[1] https://www.munichre.com/hsb/en.html

[glinscott]

Thanks, yes the capstan animation is one of my favorites :).

Great point on steel not being an option, I should have mentioned that.

RE: Hartford Steam Boiler Inspection - cool, thanks for the details!