Link to the seminal book on rocket mass heaters, still the most highly ranked book on the subject at Amazon. As far as I can tell, it's a legit distro of the pdf (per a couple of forums on the subject). The author claims to cut firewood requirements from 4 cords per winter down to 2/3 cord. All for $50 in salvaged parts and a weekend's effort. I'm looking hard at this.
The pdf opens onto a couple of blank pages. Scroll down a bit...it's there.
Rocket Mass Heaters
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