I love antique art books, especially art supply catalogs and instructional materials.
The 19th-century book, The Art of Decorative Design, discusses symmetry in nature and botany when designing decorative collectibles, motifs, etc. I just skimmed around honestly, so there’s definitely more to it than that. I saw another chapter that talked about how to express emotion in decorative design which looked interesting too. You can check out the entire book here.
There were a few illustrations that caught my eye, so I cropped and brightened them up a bit for you to use. I thought these would make great stencil designs for screen printing. You could also use them for invitations, playing card designs, stamp designs, mixed media painting, and other fun stuff.
SEO/Copy Editor/Former visual merchandiser and retail buyer/Hobby Artist/History Nerd