Looking at the wonderful close-up image by Tilman Paulin on the front page - in the feature "Looking Back On 2015" - got me to thinking. Is there anything in nature smoother and more perfectly formed than the cornea of our eyes? That dome shape is absolutely perfect. Even ice formed on still water has some imperfections. Perhaps the surface of a lens or high-quality machine part will be more perfect but what in nature? I know, too much time on my hands. But sometimes my mind decides to take a walk on its own. I just go along for the ride.