The $29.99 all-metal desktop Stirling engine kit is one of the simplest. It can be assembled in 15 minutes and is recommended for ages 14 and up. Also for $29.99 is the Exploring Kid Steam Engine Kit.

When your steam engine build requires multiple microscopes, including those of the scanning electron variety, you know you’re building something really, really tiny. All of the usual tiny ...

But instead, Erie scrapped all three by 1933. The most powerful steam locomotive is indeed an impressive engine, whose ...