Our 1920's era house is heated by hot water radiators; the boiler is fueled by fuel oil. Once a month, the fuel oil truck stops by to top off our tank so we don't forget to check on our supply and risk running out. Craig, the fuel delivery guy, listens through a pipe as he pumps the fuel to hear when it is getting close to the top of the tank.
The fuel tank is inside, in the basement. It holds 250 gallons total and Craig filled it with 225 gallons today. If I remember correctly, that is almost double what it took last month--it sure goes fast in this subzero weather. Behind the tank you can see the limestone foundation of our house- it is 1 1/2 feet thick. All the basement walls have been insulated and dry-walled except for the furnace room. The finished walls are much cozier, but not nearly as charming as the bare limestone.
The boiler was once converted to fuel oil from coal. Someday we hope to convert it again, to geothermal.
Rog and I spent much of our holiday weekend cleaning the basement - it hadn't really been dealt with since we moved in a year ago. A lot of stuff hadn't ever been unpacked and we lived without it just fine. A big load of stuff we didn't need went to Salvation army and the rest got organized in bins on shelves. The thick foundation walls make for deep window sills where inevitably some miscellaneous things get stored.