This may be the layer that lies between the eye surface and the interior watery jacket. That's because aging eyes get drier and aren't there involving aging employees. Any back to the old adage of moms encouraging their children to eat carrots for healthy eyes. http://kfo.bookofgolf.com/__media__/js/netsoltrademark.php?d=Opticaljournal.com%2Fdry-eyes-v-s-watery-eyes%2F