Chicago House Wrecking Company · Chicago House Wrecking Company · leaf 29
r 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 the pulleys,it opens the door in the hack of the boiler and thedraft is allowed to pass right… … By cutting off the draft in this way, the fire will immediatelystart to go down and as soon as it gets down below a certainpoint, the diaphragm will be drawn down again and thiswill reverse the conditions and the doors will be opened or closedin the opposite order. It will be readily seen that an…
