Author here. The beam engine created power from steam, and was a key part of the early Industrial Revolution. The article is a deep dive into the engine: how it works, the history behind it, and the engineering tradeoffs the builders faced. There are quite a few interactive figures that I hope make the concepts easier to see.

This reminds me a lot of the articles at: https://ciechanow.ski/archives/

Not just in terms of presentation, but also quality.

Amazing!

Really cool site! Did you create the animations with videos of assemblies in a CAD package? Very noice!!!