In all the instructions about how to hatch eggs in an incubator it is said to run a certain temp for the duration of incubation but to raise the humidity a significant amount during the last three days of incubation. It makes me wonder how the hen raises the humidity during the last three days of natural incubation? Can’t seem to find an answer on the web, only more charts of recommended days, temps and humidity levels. Hope to hear from someone very soon, it is a question that’s been buggin me for quite a while. Thanks.