6 days

Day 6 of incubation, blood vessels becoming more obvious, entire egg except air cell getting darker:

An embryo that died within the first week of incubation, showing the characteristic "blood ring":

An infertile egg. As the egg ages, the albumen (egg white) thins out and the yolk comes closer to the shell. That's that dark area you see in this egg. In a fresh egg, the "yolk shadow" isn't nearly this obvious:

An infertile egg with a very speckled shell, I'm showing you this just because it's interesting:

An egg that is hatching!:

There were three chicks hatched this morning, they should be done by tomorrow afternoon. I shot some QuickTime video of one while it hatched (through the hatcher door, through the wire, with a flashlight and my camera). The quality isn't good and they are huge files but I can post them here if anyone wants to see them.. let me know. I'd need to find a way to shrink them down, maybe turn them into zip files or something.