"In small rooms... the chimney often smokes unless the door or window be open, not only because the fire devours and carries off a large quantity of the air of the room, but also because the fire requires a continual supply of air for its support; so that, if a proportional quantity of air which the fire consumes and sends up the chimney does not enter the room (which it cannot do in small rooms with a large fire), the fire languishes, and the smoke increases, since flame is nothing more than a kindled smoke, and smoke is only an extinguished flame, or, at least, not yet kindled."