My Uncle had a gravity "octopus" woodburner in the farmhouse basement until sometime in the early 1980's when he switched to propane. Narrow little stairway down to a cramped cellar several times a day to feed the beast.... Cutting cordwood all summer on the hills (and some of that was before hydraulic splitters).
I've got picture of Grandpa with his IH pick-up parked next to the foundation of a house. Also in the picture is the top half of my mom (as a young girl) emerging from the bulkhead doors.
Grandpa was a mason and building a house in his spare time. He had to sell the old place to raise the money to buy supplies for the new house, so as soon as the basement was done, they moved in. That house, and 2 more, were built with used brick that they used to give away back then.
My house used to have a "hybrid" forced air/gravity furnace...more or less.
The original gas valve had a "locking tab" on it that allowed the user to open the valve manually and light the burners during a power outage. Since there was no power for the blower, it basically worked like a gravity system.
Of course, no blowers meant nothing (except for gravity) to take the heat away from the heat exchanger, so there was a pretty strict duty cycle listed in the manual. Obviously it was completely dependent on the user to adhere to the duty cycle. Not the safest set-up ever designed.
When the furnace was 30-something years old, the gas valve went bad and I couldn't afford a whole new system, so I had to have the valve replaced. The repair guy laughed when I asked if he could get an "original" gas valve so that I wouldn't lose that feature. He mentioned a "code" or something like that. ;-)
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