I had 7 chicks hatch all together. All from Thursday night to Friday night about 10 PM. I had 3 eggs left, and I took them out this morning. One was never fertile, and the other two were developed, but there was an awful lot of liquid in the shell. They could have drowned. They never pipped.
On Friday morning, 2 chicks had hatched and 1 more had pipped the shell. Friday night, that chick had still not hatched. I was concerned that it was dead because 4 others had hatched before this one. I looked real close and saw the membrane moving in and out. The chick was breathing. I looked in FAQ's on BYC and followed instructions on when to intervene, and it worked. The chick is alive and doing well. It may have hatched on its own, but I wasn't going to take that chance.