Interesting facts about our eyes:
It is enough to stay in a dark room for one minute to increase our eye sensitivity to light 10 times, and after waiting 20 minutes - about 6 thousand times. The eye of a human who spends about 4 hours a day working with computer changes it focus from keyboard to screen about 20 thousand times. The human eye is able to see a candle's fire in the dark from a 2km distance! The average person blinks every 10 seconds. Blink takes around 1-3 seconds. It comes out that we spend blinking 25 minutes out of 12 hours. Children blink less, 1-4 times per minute. Eyes weighs about 8 grams. Human eyes with good lighting are able to separate 10 Million color shades. First few days newborns can't focus on things that are further than 25 centimeters from them.