Why do billions of people still not have glasses? November 19, 2019 at 04:55PMhttps://https://ift.tt/2QyEqVl It's thought 2.5 billion people could benefit from technology first developed in the 1200s.

It's thought 2.5 billion people could benefit from technology first developed in the 1200s.

from BBC News - World https://ift.tt/2QyNLMJ