Candling an egg

I'm not trying to hatch chicks, but I had the flashlight this evening and picked up a couple of blue eggs from the (still faithfully laying) araucana mutts (the nondescript half-tailed black hens which have become our favorties for their freindly personalities). So I decided to candle an egg. Very cool watching the yolk slide around. The egg looked like a map of Jupiter with the yellows and reds and stripes on the eggs.
Not sure what the circle at the wide end is; I guess maybe the air cavity at the end? It's interesting that it can't be seen at all from the outside in normal light.
