Q. Why does a chimney smoke, if the draught be slack?
A. Because, unless the current of air up the chimney be very powerful, it cannot buoy the smoke up through the flue.
Q. If the opening of a chimney be too large, what remedy can be applied?
A. The chimney-place must be contracted.
Q. Why will contracting the chimney-place prevent its smoking?
A. As the air will then pass nearer the fire, it will be more heated, and fly up the chimney much faster.
Q. Why do almost all chimneys smoke in gusty weather?
A. The gust (blowing the air away from the top of the chimney) removes (for a time) all resistance to the smoke: but when the wind lulls again, the resistance of the air suddenly returns—the draught is checked—and a puff of smoke rushes into the room.
Q. What is the use of a chimney-pot?