Jamieson, Fausset and Brown on Jeremiah 36:22

22. winter house--(Am 3:15).

ninth month--namely, of the religious year, that is, November or December.

fire on ... hearth--rather, the stove was burning before him. In the East neither chimneys nor ovens are used, but, in cold weather, a brazen vessel containing burning charcoal; when the wood has burned to embers, a cover is placed over the pot to make it retain the heat.