I made a "window" in the large end of one of the eggs and put a small piece of clear tape over it so that I could watch. I have done this before with no ill effects. What it looks like is that when the chick breaks the membrane, it does not begin breathing immediately. It takes a breath, then pauses awhile before taking another breath. The pauses come fewer and further apart until breathing is regular. I had a good view of the beak last night and then the chick turned to the side of the shell. I would imagine pipping will begin any time. If I recall correctly, I set them late Friday night on the 8th so tonight is the night. I will be sure and take some photos. Good luck back at you. This has been fun.