I took these photos of steam-powered road vehicles at Chatham Dockyards during a recent historic transport event. It's good to know that when the electricity fails we'll still be able to flatten roads.
What's the attraction of steam power? These machines can be hypnotic to watch - literally given the number of spinning parts; they're noisy, dirty and dangerous and all of this draws and holds your attention. If you understand only a fraction of the underlying principles then it's clear that they have to be the shape they are - this is form completely following function. Yet the engineers still managed to embed flourishes and appealing shapes into the structure.
These are also machines that should have rusted, fallen apart or failed long ago - nowadays who expects even a car to last more than a few years? The fact that these engines are still running now is the reason I am in awe of both the original designers and the enthusiasts who restore and maintain them today.