be real careful around the chimneys. my buddie was standing right next to one made of stone when it fell. crushed a wheel barrow into the ground.
he was burning brush at the opening and the overly hot fire weakened the round bar 3" in diameter that was serving as a lintel. there was no warning, he said he felt the thud.
i've seen old house with two, opposite facing, chimneys?
good luck hunting the area!