https://www.flickr.com/search/?tags=bookcollectionbiodiversity < A treasure trove of The Internet Archive's book images taken from a variety of out-of-copyright works, with a focus on natural history (though there are other things!). Click through on each image for a link to the source book on archive.org that you can view with their book viewer, or download.
I also just found this one - makes science sound scandalous 😁
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