This lecture-exhibit, titled Why We Think Nature Beautiful, has been on the Web for years. During all that time, I've been intending to read it. I haven't done so yet, but I'm still hoping to. In the meantime, I'm glad it's still here.
I'm thinking of doing a study here of the Maestà (1308-11) by Duccio di Buoninsegna.
For an idea of just what a good idea that might be, take a look at the front and back of this complex, extraordinary work of art.
We have the privilege of viewing each leaf of the Burnet Psalter, 15th century, online. The initial leaf of the psalter proper is here, where the miniature that accompanies Psalm 1 shows an elderly King David playing his harp for the Lord.