The rare book library at Yale University has no windows because the walls are made of translucent marble.

mlgimmortal:

crookedwiings:

cloudfreed:

bbcbecausebenedictcumberbatch:

did-you-kno:

Source

*Heavy breathing*

because direct unfiltered sunlight may damage the older books and age them more quickly

*EXTREME HEAVY BREATHING*

IM ALWAYS A SLUT FOR LIBRARIES