Our first bunch of chicken eggs (29) were due to hatch yesterday.  They are black Langshan's and the eggs were dark and hard to see through when candling. 
Unlike our ducklings, which we have had good luck incubating, I was never quite sure if they were on target or not.  There were a lot that were dark inside at the end with what appeared to be good air cells and we just kept the temps and humidity where they needed to be and our fingers crossed.
Late last night before I went to bed I checked them one last time and there were two noticeable pips.
Those two hatched early this morning (were out when I checked at 4:00 am) and one more came out this morning.  
We have several more that are rocking and/or pipped. I think we may have a few that we should have chucked earlier in the process, but being ever the optimists we left them til the end.
I will post the final number and pictures when all are hatched!
Deb