(under subclass 151) Apparatus in which the combining tube of the jet pump is a flue or stack of a furnace and the jet acts to increase the draft effect of the flue or stack.
(1) Note. Where the operation of the device necessarily involves a treatment of the flue gases, such as the entrainment of air or air and steam to effect combustion of
unconsumed particles of fuel, or where any treatment of the fuel gases not merely a pumping effect is involved, or where the combination embraces elements of a furnace mechanism of greater scope than herein defined, the device is classified in appropriate subclasses of Class 110, Furnaces; see especially subclasses 150, 160, and indented subclass. Compare Class 261, Gas and Liquid Contact Apparatus, subclass 24, and indented subclasses.
