.~.~> Chambers are movably or removably mounted retorts
(under subclass 120) Apparatus including means forming distinct chambers that communicate with each other or are formed in the same heating apparatus.
SEE OR SEARCH THIS CLASS, SUBCLASS:
128+, for plural work chambers having heating means and through which work is progressed or moved mechanically; and 163+ for plural structurally related work chambers in which work is heated by contact with combustion products.
SEE OR SEARCH CLASS
202, Distillation: Apparatus,
113+, for plural structurally related, externally heated chambers in which carbonaceous materials are broken down by heat.