I had the same problems seeing through my brown eggs. The "blob" eggs I watched for quite awhile and saw movement. I moved the flashlight around the egg until I found the light spot. I think the light spot was probably the yolk sack but since it was lighter I could see the movement in the egg. What I would see most times was similar to a heartbeat or a breathing motion. I left the blobs in, they had developed fine but I think it was humidity issues that prevented hatching.
Janet
Janet
