There’s more than a million, and they’re all free.
The thing about books is that they’re not very much good when they’re closed and wedged into a shelf. At the same time, no sensible curator would let you put your grubby little mitts on a 250-year-old treasure. So, starting in 2013, the British Library began scanning thousands of books from the 17th, 18th and 19th Centuries, and has now made all of the images contained within them free to download (they’re all well out of copyright).
The curation is a bit all over the place, but there are some loose categories. In “Cycling,” for instance, you can see strange inventions of yore like a bicycle that uses a crankshaft and bevel gears rather than a chain, and another that features oddly asymmetrical wheels. You can also see things like old designs for saddles.
“Technology” provides helpful diagrams of early war-making machines, production machinery and scientific inventions.
The “Architecture” section is perhaps the densest, and features tons of lovely etchings.
The “Highlights” section is good for random browsing. Here you’ll find strange furniture and product designs or random stuff, like what people thought sharks used to look like.
Get started here.