Originally Posted by Chubulor

I've had the same experience with Google Books. I downloaded Florian Cajori's "History of Mathematics" as a PDF a few months ago for free, and to my dismay every single mathematical symbol and every equation or inequality had been rendered into garbage characters. So if I was interested in Johann Bernoulli's childhood pet, I had no trouble finding that information, but the description of his mathematical work was illegible. I think it has to do with the OCR used by the person who originally scanned the work...Google doesn't scan most of those books themselves, so it's possible that some of them are scanned in a way that preserves non-Roman symbols.