1) Chamber 2) Fireroom 3) Stokehold 1) Fireroom 2) Stokehold 
• (n.) The mouth to the grate of a furnace; also, the space in front of the furnace, where the stokers stand.
Stoke'hole` noun The mouth to the grate of a furnace; also, the space in front of the furnace, where the stokers stand. 
a hole in a furnace through which the fire is stoked.