Got Thermal Mass?
Thermal mass is a heat sink. It equalizes to the temperature around it. But based on how much mass there is, this equalizing (change of temperature) can happen much slower than the surrounding environment.
Lots of different stuff can function as thermal mass: rocks, bricks...
My Homemade Incubator
I've enjoyed reading about all the homemade incubators many of you have made. So being the mechanical type I am... I thought... "hey, I could build that!". So I decided instead of getting day old chicks to begin my family's adventure into raising a small backyard...