How did we even discover glasses?

well I hope so xD

lenses occur commonly in nature. for example, water droplets. So does glass. go figure out the rest

Well, I'm guessing the concept of glasses was at least slightly based on the telescope (or vice versa) with its outward, inward lenses to make things appear closer and further away and such. But I'm not sure.

Actually, a roman emperor started using emeralds too see better in the coliseum.