1. About ½ of our brain is involved in the seeing process. Humans are very much visual animals.
2. The external muscles that move the eyes are the strongest muscles in the human body for all
that they have to do. They are 100 times more powerful than they need to be.
3. The eyeball of a human weighs approximately 28 grams or 1 oz.
4. Cataracts formation is a normal aging phenomenon and so all animals in the kingdom that see
will get cataracts if they live long enough.
5. On a dark night a human eye can see a candle flickering 30 miles away.