Artists have long employed symbols as a form of visual shorthand to convey their ideas. The earliest of these, such as those employed in European cave art of 30,000 years ago, remain a mystery. But the meaning of even those from a few hundred years ago can be ambiguous. This is an issue for those engaged in logo design work, which typically relies on the need to pack meaning into a small area with just a few lines and colors, often invoking symbolism to add depth to the imagery. But where do all these symbols come from? And where can you find collections of them, from which to draw inspiration that can lead to a reinterpretation for modern viewers?
One source is old books, such as Devises et emblemes, anciennes et modernes (symbols and emblems, old and new) by Heinrich Offelen. Published in 1693, this is available for online perusal or download on the openlibrary site and is worth browsing when you're in need of some fresh creative directions. I've included a few sample pages below of just the emblems, although the book also includes descriptions of the meaning of each in several languages.