I had my class dissect the eggs that didn't hatch (which was all of them). We were able to identify what day they quit on. Most were early quiters like day 4-6. Probably due to me moving the eggs from the dog house (where the hen layed them) to the incubator. But one egg looked like day 16 or 17. It had feathers, beak, feet. I almost started crying. Why on earth would it die on day 16 or 17? Could it have been the power outage we had for 6 hours due to a freak lighting storm?