The venerable British Library has made thousands of archival images available online, for free. They’re PD – I’m so excited about this that I’m resorting to using copyright jargon. PD is “public domain.” You and I are the public. The images are now in our domain. This one’s in my domicile, because I completely dork out about 19th century and early 20th century reference books. Like this one. A student’s geology manual from the 1870s.