Chicago House Wrecking Company · Chicago House Wrecking Company · leaf 28
leys to the damper doors on the boiler itcontrolls the) drafts. When the pressure in the boiler gets up to a cer-tain point beyond this reasonable limit, this rubberdiaphragm forces the beam upward and closes thedraft door in the bottom of the boiler and at thesame time, owing to the arrangement of…
